Publications by authors named "Zhifang Du"

6 Publications

  • Page 1 of 1

Resolving Atomic-Scale Interactions in Non-Fullerene Acceptor Organic Solar Cells with Solid-State NMR Spectroscopy, Crystallographic Modelling, and Molecular Dynamics Simulations.

Adv Mater 2021 Nov 24:e2105943. Epub 2021 Nov 24.

University of Lille, CNRS, Centrale Lille Institut, Univ. Artois, UMR 8181, Unité de Catalyse et Chimie du Solide, Lille, F-59000, France.

Fused-ring core non-fullerene acceptors (NFAs), designated "Y-series", have enabled high-performance organic solar cells (OSCs) achieving over 18% power conversion efficiency (PCE). Since the introduction of these NFAs, much effort has been expended to understand the reasons for their exceptional performance. While several studies have identified key optoelectronic properties that govern high PCEs, little is known about the molecular level origins of large variations in performance, spanning from 5 to 18% PCE, e.g., in the case of PM6:Y6 OSCs. Here, we introduce a combined solid-state NMR, crystallography, and molecular modelling approach to elucidate the atomic-scale interactions in Y6 crystals, thin films, and PM6:Y6 bulk heterojunction (BHJ) blends. We show the Y6 morphologies in BHJ blends are not governed by the morphology in neat films or single crystals. Notably, PM6:Y6 blends processed from different solvents self-assemble into different structures and morphologies, whereby the relative orientations of the sidechains and end groups of the Y6 molecules to their fused-ring cores play a crucial role in determining the resulting morphology and overall performance of the solar cells. The molecular-level understanding of BHJs enabled by this approach will guide the engineering of next-generation NFAs for stable and efficient OSCs. This article is protected by copyright. All rights reserved.
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http://dx.doi.org/10.1002/adma.202105943DOI Listing
November 2021

A High-Performance Solution-Processed Organic Photodetector for Near-Infrared Sensing.

Adv Mater 2020 Jan 12;32(1):e1906027. Epub 2019 Nov 12.

Center for Polymers and Organic Solids, University of California, Santa Barbara, CA, 93106, USA.

Sensitive detection of near-infrared (NIR) light enables many important applications in both research and industry. Current organic photodetectors suffer from low NIR sensitivity typically due to early absorption cutoff, low responsivity, and/or large dark/noise current under bias. Herein, organic photodetectors based on a novel ultranarrow-bandgap nonfullerene acceptor, CO1-4Cl, are presented, showcasing a remarkable responsivity over 0.5 A W in the NIR spectral region (920-960 nm), which is the highest among organic photodiodes. By effectively delaying the onset of the space charge limited current and suppressing the shunt leakage current, the optimized devices show a large specific detectivity around 10 Jones for NIR spectral region up to 1010 nm, close to that of a commercial Si photodiode. The presented photodetectors can also be integrated in photoplethysmography for real-time heart-rate monitoring, suggesting its potential for practical applications.
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http://dx.doi.org/10.1002/adma.201906027DOI Listing
January 2020

Relevance of clinical features in the prognosis of bronchopulmonary dysplasia in premature infants.

Exp Ther Med 2017 Oct 22;14(4):3433-3440. Epub 2017 Aug 22.

Newborn Care Center, Affiliated Bayi Children's Hospital, Clinical Medical College in PLA-Army General Hospital, Southern Medical University, Beijing 100007, P.R. China.

The aim of this study is to determine the accuracy rate of bronchopulmonary dysplasia (BPD) diagnosis and risk factors of short-term poor prognosis for premature infants. This study analyzed the clinical data of 81 premature infants (<32 weeks gestational age) with BPD, who were on oxygen therapy >28 days, and survived >36 weeks (corrected age). Outcome measures included treatments, conditions on the 28th day after birth, oxygen therapy conditions at the 36th week, occurrence of any serious complications during hospital stay. The major risk factors affecting prognosis were ventilation duration, duration of oxygen therapy, application of steroids, hypothyroidism and severity of BPD (all P<0.05). Interventions for complications (n=53) resulted in ceased inhalation of oxygen in 12 infants, improvement of symptoms in 26 infants, and were ineffective in 15 infants. BPD prognosis can be improved by shortening the duration of invasive ventilation and correcting thyroid function.
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http://dx.doi.org/10.3892/etm.2017.4985DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5639336PMC
October 2017

[Imatinib is effective in a 12-month-old boy with chronic myelogenous leukemia: case report and literature review].

Zhonghua Er Ke Za Zhi 2015 Mar;53(3):194-7

Objective: To summarize the clinical characteristics of an infant with chronic myelogenous leukemia (CML) and the effects of imatinib on the case.

Method: The clinical features of an infant with CML, who was treated with imatinib in the Norman Bethune International Peace Hospital at June 2009, were retrospectively analyzed and the reports in literature were reviewed. The 1-year-old boy suffered from recurrent low-degree fever and pallor. He had a moderate anemia, distended abdomen and marked splenomegaly. Bone marrow aspiration revealed CML in chronic phase)CP). The t (9; 22))q34; q11) could be detected and BCR-ABL (p210) was positive. The boy was diagnosed as CML-CP and treated with imatinib 100 mg per day. There were 10 related papers and more than 100 child CML patients were reported as retrieved from CNKI)from its establishment to August 2014) and Wanfang Database)from its establishment to August 2014) when "Child", " Chronic" and "Leukemia" were used as keywords. And there were 30 related papers including 400 cases from PubMed Database (from its establishment to August 2014) and one detailed report of an infant with CML was retrieved when "childhood" and "chronic myeloid leukemia" "imatinib" were used as keywords. The clinical effects of imatinib in infant CML cases were analyzed and summarized based on the literature.

Result: The boy obtained a complete hematologic response (CHR) at the 6th week of diagnosis, a complete cytogenetic response (CCyR) at the 3rd month and a complete molecular response)CMR) at the 12th month without side effect. This boy grows very well and after a 62-month follow-up, his disease was stable. According to the domestic literature, 5 children CML cases aged 6 -12 years were treated with imatinib without side effects and got complete hematologic response (CHR) after 2-month-therapy. The dose, metabolic characteristics and clinical observation of imatinib can be found in foreign literature and imatinib showed good response with good tolerance in children with CML. Imatinib is regarded as the first line drug for children CML. But it may affect the development of the children.

Conclusion: The children with CML-CP had a good response to imatinib, but more experience in the treatment of children with CML with iniatinib is needed.
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March 2015

Ultrasound measurement of the corpus callosum and neural development of premature infants.

Neural Regen Res 2013 Sep;8(26):2432-40

Department of Pediatrics, NICU, the First Hospital of Hebei Medical University, Shijiazhuang 050051, Hebei Province, China.

Length and thickness of 152 corpus callosa were measured in neonates within 24 hours of birth. Using ultrasonic diagnostic equipment with a neonatal brain-specific probe, corpus callosum length and thickness of the genu, body, and splenium were measured on the standard mid-sagittal plane, and the anteroposterior diameter of the genu was measured in the coronal plane. Results showed that corpus callosum length as well as thickness of the genu and splenium increased with tional age and birth weight, while other measures did not. These three factors on the standard mid-sagittal plane are therefore likely to be suitable for real-time evaluation of corpus callosum velopment in premature infants using cranial ultrasound. Further analysis revealed that thickness of the body and splenium and the anteroposterior diameter of the genu were greater in male infants than in female infants, suggesting that there are sex differences in corpus callosum size during the neonatal period. A second set of measurements were taken from 40 premature infants whose gestational age was 34 weeks or less. Corpus callosum measurements were corrected to a gestational age of 40 weeks, and infants were grouped for analysis depending on the outcome of a neonatal behavioral neurological assessment. Compared with infants with a normal neurological assessment, corpus callosum length and genu and splenium thicknesses were less in those with abnormalities, indicating that corpus callosum growth in premature infants is associated with neurobehavioral development during the early extrauterine stage.
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http://dx.doi.org/10.3969/j.issn.1673-5374.2013.26.004DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4146107PMC
September 2013

Dynamic changes of cerebral-specific proteins in full-term newborns with hypoxic-ischemic encephalopathy.

Cell Biochem Biophys 2013 Jun;66(2):389-96

Department of Pediatrics, NICU, Bethune International Peace Hospital, Shijiazhuang Hebei, 050082, China.

The aim of this study was to observe the dynamic changes of serum brain-derived neurotrophic factor (BDNF), S-100B, and Tau proteins levels in full-term newborns with hypoxic-ischemic encephalopathy (HIE) and to discuss their significance in brain damage. Serum samples of 28 full-term newborns diagnosed with HIE and 20 controls were obtained in the first 24 h of life. Another serum samples were also taken, respectively, at 3 and 7 days of life in HIE group. The concentrations of BDNF, S-100B, and Tau proteins were measured by the enzyme-linked immunosorbent assay method. Mean concentrations of BDNF, S-100B, and Tau proteins among different time period and in different grades of HIE group were calculated and compared. Compared with the control group, serum BDNF and proteins S-100B levels in HIE group were significantly elevated in 24 h after birth (P < 0.05) and their concentrations were also significantly higher among patients with mod-severe HIE compared to those with mild HIE at 24 h and 7 days after asphyxia (P < 0.05). Regardless of whether mod-severe HIE or mild HIE, there were no significant difference of serum BDNF and proteins S-100B among the three different time periods. There was no difference in Tau protein levels between HIE group and control group, also no difference between mod-severe HIE group and mild HIE group. BDNF and proteins S-100B are up-regulated early in asphyxia neonates with HIE; and the released amount of BDNF and proteins S-100B from nerve center system correlate with the extent of encephalopathy.
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http://dx.doi.org/10.1007/s12013-012-9478-3DOI Listing
June 2013
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