Publications by authors named "Wenyao Zhang"

43 Publications

From centrosymmetric to noncentrosymmetric: effect of the cation on the crystal structures and birefringence values of (NH)AE(POF) (AE = Mg, Sr and Ba; = 2, 3 and 4).

Dalton Trans 2021 Jul 7. Epub 2021 Jul 7.

CAS Key Laboratory of Functional Materials and Devices for Special Environments; Xinjiang Technical Institute of Physics & Chemistry, CAS; Xinjiang Key Laboratory of Electronic Information Materials and Devices, 40-1 South Beijing Road, Urumqi 830011, China. and Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, China.

Fluorine-containing compounds significantly enrich the diversity of inorganic chemical structures. Here, four alkaline-earth metal difluorophosphates with different space groups, namely NH4Mg(PO2F2)3 (Cmcm) (1), NH4Sr(PO2F2)3 (P1[combining macron]) (2), (NH4)2Ba(PO2F2)4 (P2/n) (3) and Ba(PO2F2)2 (I4[combining macron]2d) (4), were synthesized and their structures were determined for the first time. 4 is not only the first alkaline-earth-metal difluorophosphate, but also the first difluorophosphate reported to crystallize in the non-centrosymmetric space group I4[combining macron]2d of the tetragonal crystal system. All of the three-dimensional (3D) structures of the title compounds consist of isolated (PO2F2)-, AE-O and NH4+ units, while the differences of the cation radius result in various arrangements of the (PO2F2)- units, which leads to diverse crystal structures and the disparate optical anisotropy of the crystals. According to the deep-ultraviolet (DUV) transmittance spectrum, 3 exhibits a short DUV cut off edge (<180 nm). Solid state 19F and 31P magic-angle spinning NMR spectroscopy was used to verify the presence of covalent P-F bonds in 3. The different size effects, as well as the coordination environments of the Mg2+, Sr2+, and Ba2+ cations, on the structures as a whole have been discussed in detail. In addition, the calculated birefringence values were observed to differ from 0.011 to 0.033 for the four compounds.
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http://dx.doi.org/10.1039/d1dt00698cDOI Listing
July 2021

Fluorine-Driven Enhancement of Birefringence in the Fluorooxosulfate: A Deep Evaluation from a Joint Experimental and Computational Study.

Adv Sci (Weinh) 2021 Jun 4:e2003594. Epub 2021 Jun 4.

CAS Key Laboratory of Functional Materials and Devices for Special Environments, Xinjiang Technical Institute of Physics & Chemistry of CAS, Xinjiang Key Laboratory of Electronic Information Materials and Devices, 40-1 South Beijing Road, Urumqi, 830011, China.

Understanding and exploring the functional modules (FMs) consisting of local atomic groups can promote the development of the materials with functional performances. Oxygen-containing tetrahedral modules are popular in deep-ultraviolet (DUV) optical materials, but their weak optical anisotropy is adverse to birefringence. Here, the fluorooxosulfate group is proved as a new birefringence-enhanced FM for the first time. The birefringence of fluorooxosulfates can be 4.8-15.5 times that of sulfates with the same metal cations while maintaining a DUV band gap. The polarizing microscope measurement confirms the birefringence enhancement by using the millimeter crystals experimentally. The theoretical studies from micro and macro levels further reveal a novel universal strategy that the fluorine induced anisotropic electronic distribution in fluorooxo-tetrahedral group is responsible for the enhancement of birefringence. This study will guide the future discovery of DUV optical materials with enlarged birefringence.
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http://dx.doi.org/10.1002/advs.202003594DOI Listing
June 2021

How Environmental Knowledge Management Promotes Employee Green Behavior: An Empirical Study.

Int J Environ Res Public Health 2021 04 29;18(9). Epub 2021 Apr 29.

School of Public Administration, Sichuan University, Chengdu 610065, China.

As environmental protection has gradually become the focus of enterprises' development, employee green behavior becomes an important and key antecedent to study this issue, but there have been less studies conducted with knowledge management. As a result, drawing on the theory of planned behavior and the organizational support theory, this study investigates how environmental knowledge practices (environmental knowledge sharing and environmental knowledge application) affect employee green behavior by using a questionnaire survey administered to 266 employees in China to reveal their complex relationship mechanism. The results show that environmental knowledge application and environmental knowledge sharing have a positive effect on employee green behavior; environmental behavioral intention mediates the relationship between environmental knowledge application and employee green behavior, and between environmental knowledge sharing and employee green behavior; green perceived organizational support positively moderates the relationship between environmental behavioral intention and employee green behavior. The findings shed new light on the development of employee green behavior literature and provide practical reference for strategies related to environmental protection for managers.
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http://dx.doi.org/10.3390/ijerph18094738DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8124686PMC
April 2021

Wearable Mixed-Reality Holographic Navigation Guiding the Management of Penetrating Intracranial Injury Caused by a Nail.

J Digit Imaging 2021 Apr 12;34(2):362-366. Epub 2021 Apr 12.

Department of Neurosurgery, Chongqing Emergency Medical Center, Chongqing, China.

Penetrating brain injury caused by a nail is an extremely rare neurosurgical emergency that poses a challenge for neurosurgeons. Nail entering the brain from the orbit and lodging within the cranial cavity is even more unusual. A 53-year-old male was found unconscious at a construction site, and brain CT revealed not only the presence of a nail beneath the inner table of the parietal bone, but also traumatic intracerebral hematoma. Consequently, accurate localization of the nail and hematoma was mandatory for surgical plan. During surgical planning, computational model reconstruction and trajectory calculation were completed using preoperative CT in 3D Slicer. Under the guidance of a head-mounted mixed-reality holographic computer, the neurosurgeon was able to visualize and interact with the hologram of the surgical plan, and intraoperative findings demonstrated that our low-cost portable wearable mixed-reality holographic navigation assisted precise localization of the nail and intracerebral hematoma, assuring less injury to the already compromised brain. After the surgery, the patient could obey commands, and postoperative imaging ruled out the possibility of brain abscess during follow-up. To the best of our knowledge, this is the first report on using a low-cost wearable mixed-reality holographic navigation to guide the management of penetrating intracranial injury caused by a nail.
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http://dx.doi.org/10.1007/s10278-021-00436-3DOI Listing
April 2021

Sampling and Analysis in Flow: The Keys to Smarter, More Controllable, and Sustainable Fine-Chemical Manufacturing.

Angew Chem Int Ed Engl 2021 Apr 3. Epub 2021 Apr 3.

Department of Chemistry and Biomolecular Sciences, Centre for Catalysis Research and Innovation (CCRI), University of Ottawa, 10 Marie Curie, Ottawa, ON, K1N 6N5, Canada.

Process analytical technology (PAT) is a system designed to help chemists better understand and control manufacturing processes. PAT systems operate through the combination of analytical devices, reactor control elements, and mathematical models to ensure the quality of the final product through a quality by design (QbD) approach. The expansion of continuous manufacturing in the pharmaceutical and fine-chemical industry requires the development of PAT tools suitable for continuous operation in the environment of flow reactors. This requires innovative approaches to sampling and analysis from flowing media to maintain the integrity of the reactor content and the analyte of interest. The following Review discusses examples of PAT tools implemented in flow chemistry for the preparation of small organic molecules, and applications of self-optimization tools.
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http://dx.doi.org/10.1002/anie.202102009DOI Listing
April 2021

Intelligent Multidimensional Purity Analysis and Confirmation Tool for Multiple Attribute Analysis.

Anal Chem 2021 03 19;93(8):3905-3913. Epub 2021 Feb 19.

Flow Chemistry Facility, Centre for Catalysis Research and Innovation (CCRI) and Department of Chemistry, University of Ottawa, 10 Marie Curie, Ottawa, Ontario K1N 6N5, Canada.

Chiral active pharmaceutical ingredients (APIs) are known to bind to chiral biological targets with better on-target specificity than achiral ones. However, the methods of synthesizing such APIs stereoselectively require the exhaustive optimization of multiple quality attributes of an asymmetric synthesis, wherein all critical quality attributes (for example, chemical and stereochemical purity of the API) are to be optimized in parallel and ideally from the beginning of the drug development program. A multidimensional liquid chromatographic tool capable of simultaneously measuring multiple quality attributes from a single analytical injection is reported. The tool is designed for the recirculation of chromatographic eluent bearing an analyte of interest through one or more stationary phases using a new and uniquely designed heart-cut valve. The iterative measurement of a target analyte from just one single injection will help scientists identify whether an unknown impurity is formed during reaction or during analysis. This chromatographic tool is particularly useful in the discovery of on-analysis artifacts, which is a resource-intensive exercise involving the identification, synthesis, and injection of impurity standards, all of which delay the drug development program.
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http://dx.doi.org/10.1021/acs.analchem.0c04652DOI Listing
March 2021

Fine-Tuning the Spring-Like Motion of an Anion-Based Triple Helicate by Tetraalkylammonium Guests.

Angew Chem Int Ed Engl 2021 Apr 10;60(17):9389-9394. Epub 2021 Mar 10.

Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of the Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xi'an, 710069, China.

Supramolecular springs are a class of molecular devices that may provide implications to the macroscopic spring behavior from the molecular level. Helical structures are suitable molecular springs because the specific twisting of the helical strands can cause spring-like (extension-contraction) movement along the axis upon external stimuli. Herein we report an anion-based triple-helicate spring, which can undergo reversible contraction-extension motion through introduction and removal of tetraalkylammonium cations, including TMA and analogous irregular tetrahedral cations bearing different alkyl chains, while the relative orientation of the two phosphate ions changes to facilitate guest inclusion. Notably, the degree of contraction (shortening of the helical pitch) can be fine-tuned by varying the shape and size of guest cation. However, with the larger cations (TEA , TPA and TBA ), the meso-helicate configuration is obtained, which interconverts with the helicate by addition/removal of TMA ion.
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http://dx.doi.org/10.1002/anie.202100294DOI Listing
April 2021

Multiple Transformations among Anion-based AL Assemblies: Bicapped Trigonal Antiprism AL, Tetrahedron AL, and Triple Helicate AL (A = Anion).

J Am Chem Soc 2020 12 3;142(50):21160-21168. Epub 2020 Dec 3.

Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of the Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xi'an 710069, China.

The construction of sophisticated, high-nuclearity polyhedral cages is an attractive yet challenging task in supramolecular chemistry. Herein we report the anion-coordination-driven assembly (ACDA) of a series of AL architectures ("A" denotes anion, L is ligand, = 1, 2, 4) with a biphenylene-spaced -(urea) ligand including triple helicate AL (), tetrahedron AL (), and the octanuclear, bicapped trigonal antiprism (or parallelepiped) AL (). Among them, is held by 96 hydrogen bonds, the largest number ever reported in a discrete polyhedron, and encapsulates multiple guests (three tetramethylammonium cations) in three compartments. Remarkably, multiple reversible transformations of these dynamic assemblies have been realized by alternation of the template guest, solvent, and concentration. Furthermore, a chiral ligand () with carbon stereocenters at both termini of the -(urea) backbone was designed and assembled with phosphate to form the enantio-pure triple helicate or tetrahedron. The chiral amplification effect in the tetrahedral complex is significantly larger than that in the triple helicate as a function of the point chirality.
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http://dx.doi.org/10.1021/jacs.0c10346DOI Listing
December 2020

K(POF)(SO): first fluorooxophosphorsulfate with mixed-anion [SO] and [POF] groups.

Dalton Trans 2020 Dec;49(48):17658-17664

CAS Key Laboratory of Functional Materials and Devices for Special Environments, Xinjiang Technical Institute of Physics & Chemistry, CAS, Xinjiang Key Laboratory of Electronic Information Materials and Devices, 40-1 South Beijing Road, Urumqi 830011, China.

Mixed-anion compounds are among the most promising systems to design functional materials with enhanced properties. Among the phosphate-sulfate species, the [SO4]2- and [PO2F2]- tetrahedra are known and give rise to structural versatility. However, to date, the crystal structures of phosphate-sulfates with the coexistence of two distinct anion groups ([S2O7]2- and [PO2F2]-) in one compound are unknown. Here, a novel type of fluorooxophosphorsulfate, K4(PO2F2)2(S2O7) (KSPOF), is designed and synthesized via a high-temperature method in a closed system. The crystal structure is derived from single-crystal X-ray diffraction (C2/c, a = 13.000(10) Å, b = 7.5430(10) Å, c = 19.010(10) Å, β = 130.070(10)°, and Z = 4). It is the first fluorooxophosphorsulfate with mixed-anion building units ([S2O7]2- and [PO2F2]-) and a unique drum-like cluster was found, which enriches the diversity of structures for fluorooxophosphorsulfate systems. Furthermore, the theoretical calculations indicate that KSPOF possesses moderate birefringence, which mainly originates from the distorted [PO2F2]- tetrahedron.
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http://dx.doi.org/10.1039/d0dt03307cDOI Listing
December 2020

Numerical investigation of the solute dispersion in finite-length microchannels with the interphase transport.

Electrophoresis 2021 Feb 22;42(3):257-268. Epub 2020 Nov 22.

MOE Key Laboratory of Thermo-Fluid Science and Engineering, School of Energy and Power Engineering, Xi'an Jiaotong University, Xi'an, P. R. China.

This paper utilizes a combined approach of the convection-diffusion theory and the moment analysis to conduct a comprehensive investigation of the solute dispersion under the influence of the interphase transport in finitely long inner coated microchannels. The present work has threefold novel contributions: (1) The 2D solute concentration contours in the stationary phase are calculated for the first time to facilitate the understanding the role of the interphase transport in the solute dispersion in the mobile phase. (2) The skewness of the elution curves is investigated to guide the control of solute band shape at the channel outlet. (3) The 2D diffusion-convection theory and zero-dimensional (0D) moment analysis complement each other to present a characterization of the solute dispersion behaviors more comprehensive than that by either of the two methods alone. Parametric studies are performed to clarify the effects of four major parameters related to the interphase transport (i.e., stationary phase Péclet number, interphase transport rate, partition coefficient, and stationary phase thickness) on the solute dispersion characteristics. The results from this study provide a straightforward understanding of the effects of interphase transport on the solute dispersion in finitely long microchannels and are of potential relevance to the design and operation of the microfluidics-based analytical devices.
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http://dx.doi.org/10.1002/elps.202000141DOI Listing
February 2021

The Synthesis of Warfarin Using a Reconfigurable-Reactor Platform Integrated to a Multiple-Variable Optimization Tool.

Chemistry 2020 Dec 12;26(67):15505-15508. Epub 2020 Nov 12.

Department of Chemistry, York University, 4700 Keele Street, Toronto, Ontario, M3J1P3, Canada.

Optimization of the asymmetric synthesis of warfarin, an important anticoagulant, has been evaluated using a reconfigurable reaction platform capable of performing batch, continuous flow, and plug-flow synthesis. Further, this platform has been integrated with a novel, multidimensional, multiple variable analysis tool that can evaluate multiple critical quality attributes (CQA), percent conversion and enantiomeric excess in this case, from a single injection that is repeatedly recycled in a closed loop of chromatography columns, a detector and a heart-cut valve. Further, the new, integrated analysis system also facilitates validation of each QA, providing a high-level of confidence in analytical measurements, which are obtained without operator intervention.
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http://dx.doi.org/10.1002/chem.202003700DOI Listing
December 2020

Series of Crystals with Giant Optical Anisotropy: A Targeted Strategic Research.

Angew Chem Int Ed Engl 2021 Jan 17;60(3):1332-1338. Epub 2020 Nov 17.

CAS Key Laboratory of Functional Materials and Devices for Special Environments, Xinjiang Technical Institute of Physics & Chemistry, CAS, Xinjiang Key Laboratory of Electronic Information Materials and Devices, 40-1 South Beijing Road, Urumqi, 830011, China.

The main commercially used birefringent oxides α-BaB O and YVO have the birefringences of 0.12 and 0.22. We propose a targeted high-throughput screening system to search birefringence-active functional modules (FMs) and large birefringent materials. A series of π-conjugated C-O units [C O ] , [C O ] , [C O ] , and [C O ] are discovered to be birefringence-active FMs. Theoretical and experimental studies on the crystals with C-O units confirm the feasibility of strategy. Based on this, the C-O containing compounds ranging from deep-ultraviolet to near-infrared region with large birefringence from 0.1 to 1.35 are found, and most of them break through the birefringent limit of oxides. The (NH ) C O ⋅H O crystal is grown and its experimental birefringence is 0.248 at 546 nm, which is identified as a promising UV birefringent crystal. The A-site cations play significant roles in optical properties by influencing the density and arrangement of the C-O units.
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http://dx.doi.org/10.1002/anie.202011006DOI Listing
January 2021

Advances in the discovery of novel biomarkers for cancer: spotlight on protein -glycosylation.

Biomark Med 2020 07;14(11):1031-1045

State Key Laboratory of Cancer Biology & National Clinical Research Center for Digestive Diseases, Xijing Hospital of Digestive Diseases, Fourth Military Medical University, 127 West Changle Road, Xi'an 710032, China.

Progress on glycosylation and tumor markers has not been extensively reported. Glycosylation plays an important part in post-translational modification. Previous research on glycosylation-modified biomarkers has lagged behind due to insufficient understanding of glycosylation-related regulations. However, some new methods and ideas illustrated in recent research may provide new inspirations in the field. This article aims to review current advances in revealing relationship between tumors and abnormal -glycosylation and discuss leading-edge applications of -glycosylation in developing novel tumor biomarkers.
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http://dx.doi.org/10.2217/bmm-2020-0185DOI Listing
July 2020

Two new ammonium/alkali-rare earth metal difluorophosphates ALa(POF) (A = NH and K) with moderate birefringence and short cutoff edges.

Dalton Trans 2020 Aug;49(33):11591-11596

CAS Key Laboratory of Functional Materials and Devices for Special Environments, Xinjiang Technical Institute of Physics & Chemistry, CAS, Xinjiang Key Laboratory of Electronic Information Materials and Devices, 40-1 South Beijing Road, Urumqi 830011, China.

Herein, two new ammonium/alkali-rare-earth metal fluorophosphates ALa(PO2F2)4 (A = NH4 and K) have been successfully obtained via a facile route. The introduction of F- anions with high electronegativity and non-π-conjugated species [PO2F2]- was found in the title compounds. Different from the [PO4]3- unit in phosphates, the (PO2F2)- group retains the merit of wide UV transmittance in phosphates; meanwhile, it has large polarizability anisotropy, and theoretical calculation shows that the calculated birefringences are 0.023 and 0.019 for KLa(PO2F2)4 and NH4La(PO2F2)4, respectively. More importantly, this work will contribute to the structural and functional diversity of phosphate chemistry by the exploration of the fascinating difluorophosphates.
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http://dx.doi.org/10.1039/d0dt01951hDOI Listing
August 2020

Metal-induced sensor mobilization turns on affinity to activate regulator for metal detoxification in live bacteria.

Proc Natl Acad Sci U S A 2020 06 28;117(24):13248-13255. Epub 2020 May 28.

Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853

Metal detoxification is essential for bacteria's survival in adverse environments and their pathogenesis in hosts. Understanding the underlying mechanisms is crucial for devising antibacterial treatments. In the Gram-negative bacterium , membrane-bound sensor CusS and its response regulator CusR together regulate the transcription of the operon that plays important roles in cells' resistance to copper/silver, and they belong to the two-component systems (TCSs) that are ubiquitous across various organisms and regulate diverse cellular functions. In vitro protein reconstitution and associated biochemical/physical studies have provided significant insights into the functions and mechanisms of CusS-CusR and related TCSs. Such studies are challenging regarding multidomain membrane proteins like CusS and also lack the physiological environment, particularly the native spatial context of proteins inside a cell. Here, we use stroboscopic single-molecule imaging and tracking to probe the dynamic behaviors of both CusS and CusR in live cells, in combination with protein- or residue-specific genetic manipulations. We find that copper stress leads to a cellular protein concentration increase and a concurrent mobilization of CusS out of clustered states in the membrane. We show that the mobilized CusS has significant interactions with CusR for signal transduction and that CusS's affinity toward CusR switches on upon sensing copper at the interfacial metal-binding sites in CusS's periplasmic sensor domains, prior to ATP binding and autophosphorylation at CusS's cytoplasmic kinase domain(s). The observed CusS mobilization upon stimulation and its surprisingly early interaction with CusR likely ensure an efficient signal transduction by providing proper conformation and avoiding futile cross talks.
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http://dx.doi.org/10.1073/pnas.1919816117DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7306728PMC
June 2020

Prediction of ternary fluorooxoborates with coplanar triangular units [BOF] from first-principles.

Dalton Trans 2020 May 14;49(17):5424-5428. Epub 2020 Apr 14.

CAS Key Laboratory of Functional Materials and Devices for Special Environments, Xinjiang Technical Institute of Physics & Chemistry, CAS, Xinjiang Key Laboratory of Electronic Information Materials and Devices, 40-1 South Beijing Road, Urumqi 830011, China.

Ten new ternary fluorooxoborate structures (BOF, I-X) were obtained from first-principles prediction. Coplanar aligned triangular structural units [BOF] and [BOF] like [BO] in borates were found from computational simulation. We identified new covalent coordination patterns of the F atom connected with the B atoms which were located in the bridging site, -B-F-B-. Besides, one molecular crystal with the [BOF] molecular unit was attached.
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http://dx.doi.org/10.1039/d0dt00160kDOI Listing
May 2020

Site-Selective Binding of Peripheral Chiral Guests Induces Stereospecificity in AL Tetrahedral Anion Cages.

J Am Chem Soc 2020 04 23;142(13):6304-6311. Epub 2020 Mar 23.

Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of the Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xi'an 710069, China.

Herein we report an unprecedented chiral induction of anion-coordination-driven tetrahedra (AL-type) by peripheral guests, -, -α-methylcholine and -, -β-methylcholine, which are bound along the tetrahedral edges in a highly site-specific fashion. This "peripheral templation", which has proven indispensable for the formation of tetrahedral structure, is also an effective approach to encoding chiral information to the tetrahedron. Moreover, the site-selective binding of chiral choline derivatives to the anion cage with induced one-handedness may imply applications of such metal-free, labile systems in the study of biological processes such as selective recognition of structurally similar molecules.
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http://dx.doi.org/10.1021/jacs.0c00882DOI Listing
April 2020

C-nanocoated ZnO by TEMPO-oxidized cellulose templating for improved photocatalytic performance.

Carbohydr Polym 2020 May 8;235:115958. Epub 2020 Feb 8.

College of Material Engineering, Fujian Agriculture and Forestry University, Fuzhou, 350108, China. Electronic address:

Ultrafine C-doped ZnO/carbon nanocomposites with different photocatalytic activities have been prepared using TEMPO-oxidized cellulose as a template but also as the source of carbon. The result is an enhancement of the photocatalytic activity ascribed to different phenomena: a high mesoporosity beneficial to mass transport, a thin carbon layer onto ZnO increasing the charge transfer and hydrophobicity of ZnO, a narrowing of ZnO band gap and an increase of the zinc (V) and oxygen (V) vacancies effectively suppressing of the charge recombination. These are evidenced by photocatalytic test of photodegradation of methyl orange (MO) achieved to assess and compared the different photocatalysts. The highest rate constant value of photodegradation of MO is 0.0254 min, three times higher than that of ZnO prepared without templates (0.0087 min). The present results introduce a new vision of the use of template with multiple roles in the preparation of inorganic materials and specially photocatalysts.
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http://dx.doi.org/10.1016/j.carbpol.2020.115958DOI Listing
May 2020

Noncentrosymmetric Fluorooxoborates ABOF (A = K and Rb) with Unexpected [BOF] Units and Deep-Ultraviolet Cutoff Edges.

Inorg Chem 2020 Mar 10;59(5):3274-3280. Epub 2020 Feb 10.

CAS Key Laboratory of Functional Materials and Devices for Special Environments, Xinjiang Technical Institute of Physics & Chemistry, CAS, and Xinjiang Key Laboratory of Electronic Information Materials and Devices, 40-1 South Beijing Road, Urumqi 830011, China.

The fluorooxoborates ABOF (A = K and Rb) were obtained successfully in the open system. They are the first examples containing two isolated fluorooxoborate units, [BOF] and [BOF]. To the best of our knowledge, the [BOF] unit is a new one in the reported fluorooxoborates. The title compounds exhibit short UV absorption edges (<190 nm). Furthermore, the relationship between the structures and optical properties was uncovered by theoretical calculations. More importantly, this work enriches the species for fluorooxoborate crystal chemistry.
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http://dx.doi.org/10.1021/acs.inorgchem.9b03707DOI Listing
March 2020

What influences the effectiveness of green logistics policies? A grounded theory analysis.

Sci Total Environ 2020 Apr 15;714:136731. Epub 2020 Jan 15.

School of Public Administration, Central China Normal University, Wuhan 430079, PR China. Electronic address:

Green logistics policies (GLP) are essential to the progress of green logistics, the promotion of green growth, and the fulfillment of sustainable development. However, as the uncertainty and ambiguity of factors that influence the implementation of GLP, it is urgent to explore and reveal the antecedents and functional mechanism of the effectiveness of GLP. This study adopts grounded theory method to conduct in-depth interviews, and concludes that five major factors, such as the perfection of GLP system, the green governance capacity of government, the level of perception of logistics enterprises on GLP, the level of social supervision, and the development level of logistics industry, which influence the effectiveness of GLP. And then presents the integrated model of antecedents of the effectiveness of GLP, revealing the influence path and internal mechanism of these influencing factors. It is of great significance to enhancing the effectiveness of GLP, upgrading green logistics, and achieving the green development.
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http://dx.doi.org/10.1016/j.scitotenv.2020.136731DOI Listing
April 2020

Chirality transcription in the anion-coordination-driven assembly of tetrahedral cages.

Chem Commun (Camb) 2020 Feb;56(16):2475-2478

Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of the Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xi'an 710127, China.

Enantiopure A4L4 tetrahedral cages (either ΔΔΔΔ or ΛΛΛΛ) were obtained through the anion-coordination-driven assembly (ACDA) of phosphate anions with C3-symmetric tris-bis(urea) ligands bearing chiral groups.
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http://dx.doi.org/10.1039/c9cc09752jDOI Listing
February 2020

Electrokinetic power generation in conical nanochannels: regulation effects due to conicity.

Phys Chem Chem Phys 2020 Jan 15;22(4):2386-2398. Epub 2020 Jan 15.

Key Laboratory of Thermo-Fluid Science and Engineering of MOE, School of Energy and Power Engineering, Xi'an Jiaotong University, Xi'an 710049, Shaanxi, China.

Electrokinetic power generation is a promising clean energy production technology, which utilizes the electric double layer in a nanochannel to convert the hydrodynamic energy to electrical power. Previous research largely focused on electrokinetic power generation in nanochannels with a uniform cross-section. In this work, we perform a systematic investigation of electrokinetic power generation in a conical nanochannel. For this purpose, a multiphysical model consisting of the Planck-Nernst-Poisson equations and the Navier-Stokes equation is formulated and solved numerically. In particular, we discover various regulation effects in electrokinetic power generation in conical nanochannels, which manifest as the difference in the power generation characteristics (streaming potential, streaming current and current-voltage relationship) between two opposite pressure differences of the same magnitude. These regulation effects are found to originate from the conicity of the nanochannel. Furthermore, the regulation parameters are defined to quantify the observed regulation effects. Various regulation parameters can be up to severals tens of percent under extreme conditions (e.g., large pressure difference, high surface charge density or large conicity), indicating the substantial significance of the regulation effects in electrokinetic power generation. The conclusions from this work can serve as an important reference for the design and operation of nanofluidic electrokinetic power generation devices.
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http://dx.doi.org/10.1039/c9cp05317dDOI Listing
January 2020

Merging Single-Atom-Dispersed Iron and Graphitic Carbon Nitride to a Joint Electronic System for High-Efficiency Photocatalytic Hydrogen Evolution.

Small 2019 Dec 14;15(50):e1905166. Epub 2019 Nov 14.

Key Laboratory for Soft Chemistry and Functional Materials of Ministry of Education, Nanjing University of Science and Technology, Nanjing, 210094, China.

Scalable and sustainable solar hydrogen production via photocatalytic water splitting requires extremely active and stable light-harvesting semiconductors to fulfill the stringent requirements of suitable energy band position and rapid interfacial charge transfer process. Motivated by this point, increasing attention has been given to the development of photocatalysts comprising intimately interfaced photoabsorbers and cocatalysts. Herein, a simple one-step approach is reported to fabricate a high-efficiency photocatalytic system, in which single-site dispersed iron atoms are rationally integrated on the intrinsic structure of the porous crimped graphitic carbon nitride (g-C N ) polymer. A detailed analysis of the formation process shows that a stable complex is generated by spontaneously coordinating dicyandiamidine nitrate with iron ions in isopropanol, thus leading to a relatively complicated polycondensation reaction upon thermal treatment. The correlation of experimental and computational results confirms that optimized electronic structures of [email protected] N with an appropriate d-band position and negatively shifting Fermi level can be achieved, which effectively gains the reducibility of electrons and creates more active sites for the photocatalytic reactions. As a result, the [email protected] N exhibits a highlighted intramolecular synergistic effect, performing greatly enhanced solar-photon-driven activities, including excellent photocatalytic hydrogen evolution rate (3390 µmol h g , λ > 420 nm) and a reliable apparent quantum efficiency value of 6.89% at 420 nm.
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http://dx.doi.org/10.1002/smll.201905166DOI Listing
December 2019

Cation Modulation on the Crystal Structure and Band Gap of Fluorooxoborates ABOF (A = Alkali and Mixed Alkali Metal).

Inorg Chem 2019 Oct 18;58(19):13411-13417. Epub 2019 Sep 18.

CAS Key Laboratory of Functional Materials and Devices for Special Environments, Xinjiang Technical Institute of Physics and Chemistry , CAS; Xinjiang Key Laboratory of Electronic Information Materials and Devices , 40-1 South Beijing Road , Urumqi 830011 , China.

By using cation modulation strategy, a series of fluorooxoborates ABOF (A = alkali and mixed alkali metal) were designed and successfully obtained via open high-temperature solid-state method for the first time, and single-crystal X-ray diffractions were used to determine their structures. The isolated BOF benzene-like ring structure in the title compounds is beneficial to obtain short ultraviolet absorption edge (<190 nm), which was confirmed by the UV-vis-NIR diffuse reflectance spectra. Owing to the cation size effect, there are some subtle differences in the alignment of the anionic groups. In addition, theoretical calculations were carried out to understand their electronic structures and optical properties.
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http://dx.doi.org/10.1021/acs.inorgchem.9b02307DOI Listing
October 2019

Defect-Enriched Nitrogen Doped-Graphene Quantum Dots Engineered NiCo S Nanoarray as High-Efficiency Bifunctional Catalyst for Flexible Zn-Air Battery.

Small 2019 Oct 12;15(44):e1903610. Epub 2019 Sep 12.

Department of Chemical Engineering, Waterloo Institute for Nanotechnology, University of Waterloo, Waterloo, Ontario, N2L3G1, Canada.

Flexible Zn-air batteries have recently emerged as one of the key energy storage systems of wearable/portable electronic devices, drawing enormous attention due to the high theoretical energy density, flat working voltage, low cost, and excellent safety. However, the majority of the previously reported flexible Zn-air batteries encounter problems such as sluggish oxygen reaction kinetics, inferior long-term durability, and poor flexibility induced by the rigid nature of the air cathode, all of which severely hinder their practical applications. Herein, a defect-enriched nitrogen doped-graphene quantum dots (N-GQDs) engineered 3D NiCo S nanoarray is developed by a facile chemical sulfuration and subsequent electrophoretic deposition process. The as-fabricated N-GQDs/NiCo S nanoarray grown on carbon cloth as a flexible air cathode exhibits superior electrocatalytic activities toward both oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), outstanding cycle stability (200 h at 20 mA cm ), and excellent mechanical flexibility (without observable decay under various bending angles). These impressive enhancements in electrocatalytic performance are mainly attributed to bifunctional active sites within the N-GQDs/NiCo S catalyst and synergistic coupling effects between N-GQDs and NiCo S . Density functional theory analysis further reveals that stronger OOH* dissociation adsorption at the interface between N-GQDs and NiCo S lowers the overpotential of both ORR and OER.
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http://dx.doi.org/10.1002/smll.201903610DOI Listing
October 2019

A wearable mixed-reality holographic computer for guiding external ventricular drain insertion at the bedside.

J Neurosurg 2018 10 1:1-8. Epub 2018 Oct 1.

Department of Neurosurgery, Xuanwu Hospital, Capital Medical University.

OBJECTIVE: The goal of this study was to explore the feasibility and accuracy of using a wearable mixed-reality holographic computer to guide external ventricular drain (EVD) insertion and thus improve on the accuracy of the classic freehand insertion method for EVD insertion. The authors also sought to provide a clinically applicable workflow demonstration. METHODS: Pre- and postoperative CT scanning were performed routinely by the authors for every patient who needed EVD insertion. Hologram-guided EVD placement was prospectively applied in 15 patients between August and November 2017. During surgical planning, model reconstruction and trajectory calculation for each patient were completed using preoperative CT. By wearing a Microsoft HoloLens, the neurosurgeon was able to visualize the preoperative CT-generated holograms of the surgical plan and perform EVD placement by keeping the catheter aligned with the holographic trajectory. Fifteen patients who had undergone classic freehand EVD insertion were retrospectively included as controls. The feasibility and accuracy of the hologram-guided technique were evaluated by comparing the time required, number of passes, and target deviation for hologram-guided EVD placement with those for classic freehand EVD insertion. RESULTS: Surgical planning and hologram visualization were performed in all 15 cases in which EVD insertion involved holographic guidance. No adverse events related to the hologram-guided procedures were observed. The mean ± SD additional time before the surgical part of the procedure began was 40.20 ± 10.74 minutes. The average number of passes was 1.07 ± 0.258 in the holographic guidance group, compared with 2.33 ± 0.98 in the control group (p < 0.01). The mean target deviation was 4.34 ± 1.63 mm in the holographic guidance group and 11.26 ± 4.83 mm in the control group (p < 0.01). CONCLUSIONS: This study demonstrates the use of a head-mounted mixed-reality holographic computer to successfully perform hologram-assisted bedside EVD insertion. A full set of clinically applicable workflow images is presented to show how medical imaging data can be used by the neurosurgeon to visualize patient-specific holograms that can intuitively guide hands-on operation. The authors also provide preliminary confirmation of the feasibility and accuracy of this hologram-guided EVD insertion technique.
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http://dx.doi.org/10.3171/2018.4.JNS18124DOI Listing
October 2018

Quantitative evaluation of diffusion tensor imaging for clinical management of glioma.

Authors:
Ye Li Wenyao Zhang

Neurosurg Rev 2020 Jun 12;43(3):881-891. Epub 2018 Nov 12.

Beijing Key Laboratory of Intelligent Information Technology, School of Computer Science, Beijing Institute of Technology, Beijing, 100081, China.

Diffusion tensor imaging (DTI), assessing physiological motion of water in vivo, provides macroscopic view of microstructures of white matter in the central nervous system, and such imaging technique had been extensively used for the clinical treatment and research of glioma. This review mainly focuses on illuminating the merits of quantitative evaluation of DTI for glioma management. The content of the article includes DTI's application on tissue characterization, white matter tracts mapping, radiotherapy delineation, post-therapy outcome assessment, and multimodal imaging. At last, we elucidate a synoptic presentation of DTI limitation, which is critical for physicians making DTI-based clinical decisions in glioma management.
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http://dx.doi.org/10.1007/s10143-018-1050-1DOI Listing
June 2020

ALiZnPO (A = Rb, Cs): Two Mixed Alkali Zinc Pyrophosphates Featuring a [LiZnPO] Anionic Skeleton.

Inorg Chem 2018 Sep 20;57(17):10568-10575. Epub 2018 Aug 20.

Department of Physics , Tamkang University , New Taipei City 25137 , Taiwan.

Two new isotypic diphosphates, RbLiZnPO (RLZP) and CsLiZnPO (CLZP), have been synthesized by a high-temperature solid-phase method. They both crystallize in the Pnma space group (No. 62) and have similar crystal configurations. ALiZnPO (A = Rb, Cs) consists of a [LiZnPO] anionic skeleton, which is composed of Li/ZnO tetrahedral and diphosphate groups, and the Rb or Cs atoms are located in the large hole. In this paper, we discuss the structures of the title compounds and isonomic AA'ZnPO (A = alkali metal); it is found that the ionic radii of the cations and bond angles have an effect on the symmetry of the compounds. By analysis, we found that the M/P values have some effect on the dimensionality of the anionic groups in phosphates containing PO groups. Thermal and spectral analyses are carried out on the title compounds. Besides that mentioned above, we also studied the relationship between the electronic structures and optical properties by theoretical calculations.
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http://dx.doi.org/10.1021/acs.inorgchem.8b01140DOI Listing
September 2018

Synthesis of Carbon-Nitrogen-Phosphorous Materials with an Unprecedented High Amount of Phosphorous toward an Efficient Fire-Retardant Material.

Angew Chem Int Ed Engl 2018 Jul 5;57(31):9764-9769. Epub 2018 Jul 5.

Department of Chemistry and Ilse Katz Institute for Nanoscale Science and Technology, Ben-Gurion University of the Negev, Beer-Sheva, 8410501, Israel.

Phosphorus incorporation into carbon can greatly modify its chemical, electronic, and thermal stability properties. To date this has been limited to low levels of phosphorus. Now a simple, large-scale synthesis of carbon-nitrogen-phosphorus (CNP) materials is reported with tunable elemental composition, leading to excellent thermal stability to oxidation and fire-retardant properties. The synthesis consists of using monomers that are liquid at high temperatures as the reaction precursors. The molten-state stage leads to good monomer miscibility and enhanced reactivity at high temperatures and formation of CNP materials with up to 32 wt % phosphorus incorporation. The CNP composition and fire-retardant properties can be tuned by modifying the starting monomers ratio and the final calcination temperature. The CNP materials demonstrate great resistance to oxidation and excellent fire-retardant properties, with up to 90 % of the materials preserved upon heating to 800 °C in air.
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http://dx.doi.org/10.1002/anie.201805279DOI Listing
July 2018

Controlling the Recognition and Reactivity of Alkyl Ammonium Guests Using an Anion Coordination-Based Tetrahedral Cage.

J Am Chem Soc 2018 04 10;140(15):5248-5256. Epub 2018 Apr 10.

Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of the Ministry of Education, College of Chemistry and Materials Science , Northwest University , Xi'an 710069 , China.

Caged structures have found wide application in a variety of areas, including guest encapsulation and catalysis. Although metal-based cages have dominated the field, anion-coordination-based cages are emerging as a new type of supramolecular ensemble with interesting host-guest properties. In the current work, we report a C-symmetric tris-bis(urea) ligand based on the 2,4,6-triphenyl-1,3,5-triazine spacer, which assembles with phosphate anions to form an AL-type (A = anion, L = ligand) tetrahedral cage, 3, with unusually high packing coefficients (up to 99.5% for the best substrate). Cage 3 is able to adjust its size and shape (from 136 to 216 Å) by bending of the triphenyltriazine plane. This allows it to accommodate relatively large guests. In the case of DABCO, inclusion within the cage allows the degree of methylation to be controlled and the monomethylated product to be isolated cleanly under conditions where mixtures of the mono- and dimethylated adduct are obtained in the absence of cage 3.
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http://dx.doi.org/10.1021/jacs.8b01488DOI Listing
April 2018