Publications by authors named "Ping Nie"

51 Publications

Nanospace-confinement copolymerization strategy for encapsulating polymeric sulfur into porous carbon for lithium-sulfur batteries.

ACS Appl Mater Interfaces 2015 Jun 22;7(21):11165-71. Epub 2015 May 22.

Jiangsu Key Laboratory of Materials and Technology for Energy Conversion, College of Material Science and Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing, 210016, P. R. China.

Given their high theoretical energy density, lithium-sulfur (Li-S) batteries have recently attracted ever-increasing research interest. However, the dissolution of polysulfides and uncontrolled deposition of insoluble discharge product significantly hinder the cycling stability. Herein, a nanospace-confinement copolymerization strategy for encapsulating polymeric sulfur into porous carbon matrix is presented. The morphologies and sulfur contents of carbon/polymeric sulfur (C/PS) composites could be readily tailored by controlling the copolymerization time. Confining polymeric sulfur in the porous carbon with abundant interparticle pores facilitates rapid electronic/ionic transport and mitigates dissolution of polysulfides intermediates. More importantly, the organic sulfur units dispersed in the insoluble/insulating Li2S2/Li2S phase could prevent its irreversible deposition. Such nanostructure with tailored chemistry property permits the C/PS electrodes to exhibit enhanced cycling stability and high rate capability. The nanospace-confinement copolymerization strategy features general and facial advantages, which may provide new opportunities for the future development of advanced sulfur cathodes.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acsami.5b00870DOI Listing
June 2015

High rate capability and superior cycle stability of a flower-like Sb2S3 anode for high-capacity sodium ion batteries.

Nanoscale 2015 Feb;7(7):3309-15

Jiangsu Key Laboratory of Materials and Technology for Energy Conversion (MTEC), College of Material Science and Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing, China.

Flower-like antimony sulfide structures were prepared by a simple and easy polyol reflux process. When tested as an anode for sodium ion batteries, the material delivered a high reversible capacity of 835.3 mA h g(-1) at 50 mA g(-1) after 50 cycles and maintained a capacity of 641.7 mA h g(-1) at 200 mA g(-1) after 100 cycles. Even up to 2000 mA g(-1), a capacity of 553.1 mA h g(-1) was obtained, indicating an excellent cycle performance and a superior rate capability. The mechanism of the formation of the micro-flowers was also investigated. The additive used facilitates the controlled release of the reactant to form uniform, shaped nanosheets and an optimum reaction time allows the nanosheets to self-assemble into micro-flowers.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1039/c4nr05242kDOI Listing
February 2015

Er:YAG laser versus scaling and root planing as alternative or adjuvant for chronic periodontitis treatment: a systematic review.

J Clin Periodontol 2014 Nov 10;41(11):1069-79. Epub 2014 Oct 10.

Department of Oral and Cranio-Maxillofacial Science, Shanghai Ninth People's Hospital, College of Stomatology, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology, Shanghai, China.

Aim: To perform a systematic review to evaluate the erbium-doped: yttrium, aluminium and garnet (Er:YAG) laser versus scaling and root planing (SRP) as alternative or adjuvant for chronic periodontitis treatment.

Material And Methods: We performed a literature search using six electronic databases and completed by manual searches up to July 2013. We conducted a meta-analysis as well as heterogeneity, sensitivity, subgroup and power analyses to clarify and validate the pooled results. The 3-, 6- and 12-month clinical outcomes were evaluated.

Results: Twelve eligible randomized clinical trials were finally included. Our meta-analysis showed that Er:YAG laser resulted in similar clinical improvements as SRP 3 months postoperatively. For subgroups by laser level, quality of trials and fluorescence feedback device, the results remained consistent. The 6- and 12-month observations between Er:YaG laser and SRP demonstrated no difference but inconclusive, due to large heterogeneity. The advantage of Er:YAG laser adjuvant to SRP for periodontitis treatment was not significant.

Conclusions: This systematic review indicated that the clinical efficacy of Er:YAG laser was similar to SRP 3 months postoperatively. The clinical benefits of Er:YAG laser as adjuvant to SRP was still lacking. Since Er:YAG laser has certain advantages, it could be expected to be a novel short-term alternative choice for chronic periodontitis.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/jcpe.12304DOI Listing
November 2014

[Expression of HIF-1α in the genioglossus associated with induced bilateral intermittent nasal obstruction in young rats].

Shanghai Kou Qiang Yi Xue 2014 Apr;23(2):138-42

Department of Oral and Cranio-maxillofacial Science, Ninth People's Hospital, College of Stomatology, Shanghai Jiao Tong University School of Medicine; Shanghai Key Laboratary of Stomatology. Shanghai 200011,

Purpose: To investigate the expression of HIF-1α in the genioglossus associated with induced bilateral intermittent nasal obstruction in young rats.

Methods: Thirty 4-week-old SD rats were employed and equally divided into 3 groups. In group A, both nostrils were occluded by nose plugs. In group B, the right nostril was occluded. In group C, no obstruction of the nose was performed as control group. The obstruction time was from 8 am to 12 am everyday, and the period was 21 d and 55 d. The genioglossus was taken for HE, and immunohistochemical staining was used to detect the expression of HIF-1α. The data was analyzed with SPSS 13.0 software package.

Results: The rats were sacrificed at the 21th day and 55th day, respectively. The expression of HIF-1α in group A was significantly higher than that in group B and group C, and became stronger with the increasing of obstruction time.

Conclusions: Oral breathing caused by bilateral intermittent nasal obstruction in young rats results in overexpression of HIF-1α in the genioglossus. Supported by Research Fund and Experimental Animal Fund of Science and Technology Committee of Shanghai Municipality (11140902001).
View Article and Find Full Text PDF

Download full-text PDF

Source
April 2014

Oral appliance effectively reverses Muller's maneuver-induced upper airway collapsibility in obstructive sleep apnea and hypopnea syndrome.

Sleep Breath 2015 Mar 29;19(1):213-20. Epub 2014 May 29.

Department of Oral and Cranio-Maxillofacial Science, Shanghai Ninth People's Hospital, School of Stomatology, Shanghai Key Laboratory of Stomatology, Shanghai Jiao Tong University School of Medicine, No. 639 Zhi Zao Ju Rd, 200011, Shanghai, China.

Objectives: To verify the effects of oral appliance (OA) on upper airway morphology under intraluminal pressure, identify specific sites of upper airway collapsibility that can be reversed by OAs, and determine the relationship between OA efficacy and dynamic upper airway changes using computed tomography (CT) with Muller's maneuver.

Materials And Methods: Nineteen adult Chinese patients with symptomatic mild-to-moderate sleep apnea were recruited from our sleep center. Each patient was fitted with a two-piece OA. Dynamic changes in the retropalatal and retroglossal airway were evaluated using CT at end-expiration and during Muller's maneuver, both with and without an OA.

Results: Upper airway changes in the end-expiration phase before OA placement did not significantly differ from those after OA placement. However, under intraluminal pressure induced by Muller's maneuver, OA effectively expanded the upper airway at multiple levels. In addition, OA counteracted negative intraluminal pressure more effectively in the retropalatal region than in the retroglossal region, with 95.65, 68.75, 72.41, and 78.38 % improvements in the collapsibility index of the anteroposterior dimension, transverse dimension, minimum cross-sectional area, and volume of the retropalatal region, respectively. Both nonresponders and responders to OA treatment were sensitive to the intraluminal pressure induced by Muller's maneuver. However, the collapsibility of the retropalatal airway improved significantly only in the responders, not in the nonresponders.

Conclusions: OA effectively treats OSAHS by improving upper airway collapsibility.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s11325-014-0994-9DOI Listing
March 2015

Synthesis of NASICON-type structured NaTi2(PO4)3-graphene nanocomposite as an anode for aqueous rechargeable Na-ion batteries.

Nanoscale 2014 Jun;6(12):6328-34

College of Material Science & Engineering and Key Laboratory for Intelligent Nano Materials and Devices of Ministry of Education, Nanjing University of Aeronautics and Astronautics, Nanjing, 210016, P. R. China.

A new solvothermal strategy combined with calcination has been developed to synthesize NaTi2(PO4)3-graphene nanocomposites. X-ray diffraction, thermogravimetric analysis, field-emission scanning electron microscopy and transmission electron microscopy were performed to characterize their microstructures and morphologies. It was found that NASICON-type structured NaTi2(PO4)3 nanoparticles with highly crystallinity were homogeneously anchored on the surface of conducting graphene nanosheets, forming a two-dimensional hybrid nanoarchitecture. A possible growth mechanism was also discussed based on time-dependent experiments. When used as anode materials for Na-ion batteries, the nanocomposites exhibited excellent electrochemical performance with high-rate capability and excellent cycling stability in 1 M Na2SO4 aqueous electrolyte. The electrode delivered high specific capacities of 110, 85, 65, 40 mA h g(-1) at 2, 5, 10 and 20 C, respectively, and still retained 90% of the initial capacity after 100 cycles at 2 C.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1039/c3nr06730kDOI Listing
June 2014

Rational design of void-involved [email protected] nanospheres as high-performance anode material for lithium-ion batteries.

ACS Appl Mater Interfaces 2014 May 18;6(9):6497-503. Epub 2014 Apr 18.

College of Materials Science and Engineering, Key Laboratory for Intelligent Nano Materials and Devices of Ministry of Education, Nanjing University of Aeronautics and Astronautics , Nanjing, 210016, P.R. China.

A unique core-shell structure of [email protected] ([email protected]) composite with silicon nanoparticles encapsulated in TiO2 hollow spheres is synthesized by a simple hydrolysis method combined with magnesiothermic reduction method. It is found that the TiO2 shell is effective for improving the electrical conductivity and structural stability. More importantly, the well-designed nanostructure with enough empty space would accommodate the volume change of silicon during the cycling. Reversible capacities of 1911.1 and 795 mAh g(-1) can be obtained at 0.05 C and a high current rate of 1 C, respectively. After 100 cycles at 0.1 C, the composite electrode still maintains a high capacity of 804 mAh g(-1). This excellent cycling stability and high-rate capability can be ascribed to the unique core-shell nanostructure and the synergistic effect between Si and TiO2.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/am500066jDOI Listing
May 2014

Cyclin D1 overexpression is associated with poor clinicopathological outcome and survival in oral squamous cell carcinoma in Asian populations: insights from a meta-analysis.

PLoS One 2014 27;9(3):e93210. Epub 2014 Mar 27.

Department of Oral and Cranio-Maxillofacial Science, Shanghai Ninth People's Hospital, College of Stomatology, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology, Shanghai, China.

Background: The clinicopathological significance of cyclin D1 overexpression and prognosis of oral squamous cell carcinoma has not been fully quantified. We performed a comprehensive meta-analysis for evaluation of cyclin D1 overexpression in oral squamous cell carcinoma to determine the strength of this association.

Methods: Using both medical subheadings and free terms, we searched PubMed, Embase and the Institute for Scientific Information Web of Science for all eligible studies published before Nov. 2013. We retrieved 1674 citations, determining that 15 met the selection criteria. We used the odds ratio (OR) and hazard ratio (HR) as the common measures of association to quantitatively determine the correlation between cyclin D1 overexpression and outcomes of oral cancer. We performed a meta-analysis and heterogeneity, sensitivity, and subgroup analyses to clarify and validate the pooled results.

Results: The pooled results provided compelling evidence that cyclin D1 overexpression was significantly correlated with increased tumor size (OR = 1.617, 95% confidence interval [CI] = 1.046-2.498, p = 0.031), lymphoid node metastasis (OR = 2.035, 95% CI = 1.572-2.635, p<0.001), tumor differentiation (OR = 1.976, 95% CI = 1.363-2.866, p<0.001), and advancement of clinical stages (OR = 1.516, 95% CI = 1.140-2.015, p = 0.004), and adversely influenced overall survival of OSCC patients (HR = 1.897, 95% CI = 1.577-2.282, p<0.001). The strength of association varied in different oral cavity subsites.

Conclusion: Our findings indicated that cyclin D1 expression correlates with detrimental clinicopathological outcome and poor prognosis in oral squamous cell carcinoma. Our results may be useful in the management of oral cancer.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0093210PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3968091PMC
December 2015

[Evaluation of upper airway and surrounding structures in patients with obstructive sleep apnea using cephalometry combined with Muller's maneuver].

Shanghai Kou Qiang Yi Xue 2013 Dec;22(6):684-9

Department of Oral and Craniomaxillofacial Science, Ninth People's Hospital, College of Stomatology, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology. Shanghai 200011,

Purpose: To evaluate the upper airway and surrounding structures under intraluminal pressure using cephalometry combined with Muller's maneuver in obstructive sleep apnea and hypopnea syndrome (OSAHS) patients with different severity.

Methods: Thirty-nine male patients were enrolled in our department during June 2011 to February 2012. Polysomnography (PSG) and anthropometric measurements data were recorded prior to the study. The lateral cephalograms of each patient were obtained during both the end-expiration phase and Muller's maneuver phase. The patients enrolled were classified into 3 groups according to the results of apnea-hypopnea index (AHI), including mild group (n=11), moderate group (n=14), and severe group (n=14). Craniofacial and upper airway structures were measured in lateral cephalometry by application of Cassos 2001 computed aided measurement software before and after the patients practicing Muller's maneuver. The data was analysed using SAS 9.13 software package.

Results: Muller's maneuver had a great influence on the upper airway and surrounding tissue, including increased thickness of the uvula, reduction in the anteroposterior dimension of retropalatal and increased vertical distance of the hyoid bone to the mandible in all groups (P<0.05). In addition, Muller's maneuver also had an impact on the length of the upper airway, which was more significant in severe cases.

Conclusions: Cephalometry combined with Muller's maneuver can display how the intraluminal pressure function on the upper airway and surrounding tissues, and they also can distinguish some minor differences of the upper airway in patients with different security. Supported by Research Fund of Science and Technology Commission of Shanghai Municipality (11140902001).
View Article and Find Full Text PDF

Download full-text PDF

Source
December 2013

Design of a Nitrogen-Doped, Carbon-Coated Li Ti O Nanocomposite with a Core-Shell Structure and Its Application for High-Rate Lithium-Ion Batteries.

Chempluschem 2014 Jan 29;79(1):128-133. Epub 2013 Nov 29.

College of Materials Science and Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing, 210016 (P. R. China), Fax: (+86) 025-52112626.

A facile solution-based synthesis and characterization of a nitrogen-doped, carbon-coated Li Ti O (NC-LTO) nanocomposite is reported. The mesoporous TiO nanoparticles (NPTiO ) are first prepared by using nanocrystalline cellulose (NCC) as a template and subsequently transform in situ into an NC-LTO nanocomposite with a core-shell structure by using the ionic liquid 1-ethyl-3-methylimdazolium tricyanomethanide as the carbon source. Various state-of-the-art techniques, including field-emission SEM, TEM, scanning transmission electron microscopy, XRD, X-ray photoelectron spectroscopy, and thermogravimetric analysis, were performed to characterize the morphologies, structures, and compositions. Such NC-LTO nanocomposites have a well-defined LTO core and thin uniform carbon shell with a thickness of 1-2 nm. Electrochemical tests reveal that the NC-LTO nanocomposite delivers a reversible capacity of 171.5 mAh g at 0.2 C, and shows remarkable rate capability by maintaining 63 % of the capacity at 60 C (vs. 0.2 C), as well as excellent cycling stability with a capacity retention of 95 % after 300 cycles at a rate of 10 C. The excellent electrochemical performance is attributed exclusively to the well-defined core-shell nanostructure and high electric conductivity. The nanosized LTO core can significantly shorten the transport lengths of lithium ions and the admirable electric conductivity of the nitrogen-doped carbon shell can act as an "expressway" for electrons and lithium ions to transport them between the anode material core and the electrolytes.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/cplu.201300316DOI Listing
January 2014

Hierarchically porous carbon encapsulating sulfur as a superior cathode material for high performance lithium-sulfur batteries.

ACS Appl Mater Interfaces 2014 Jan 23;6(1):194-9. Epub 2013 Dec 23.

College of Materials Science & Engineering, Nanjing University of Aeronautics and Astronautics , Nanjing, 210016, P. R. China.

Lithium-sulfur (Li-S) batteries are deemed to be a promising energy storage device for next-generation high energy power system. However, insulation of S and dissolution of lithium polysulfides in the electrolyte lead to low utilization of sulfur and poor cycling performance, which seriously hamper the rapid development of Li-S batteries. Herein, we reported that encapsulating sulfur into hierarchically porous carbon (HPC) derived from the soluble starch with a template of needle-like nanosized Mg(OH)2. HPC has a relatively high specific surface area of 902.5 m(2) g(-1) and large total pore volume of 2.60 cm(3) g(-1), resulting that a weight percent of sulfur in S/HPC is up to 84 wt %. When evaluated as cathodes for Li-S batteries, the S/HPC composite has a high discharge capacity of 1249 mAh g(-1) in the first cycle and a Coulombic efficiency as high as 94% with stable cycling over prolonged 100 charge/discharge cycles at a high current density of 1675 mA g(-1). The superior electrochemical performance of S/HPC is closely related to its unique structure, exhibiting the graphitic structure with a high developed porosity framework of macropores in combination with mesopores and micropores. Such nanostructure could shorten the transport pathway for both ions and electrons during prolonged cycling.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/am4038728DOI Listing
January 2014

Interleukin-16 gene polymorphisms rs4778889, rs4072111, rs11556218, and cancer risk in Asian populations: a meta-analysis.

Genet Test Mol Biomarkers 2014 Mar 13;18(3):174-82. Epub 2013 Dec 13.

1 Department of Oral and Cranio-Maxillofacial Science, Shanghai Ninth People's Hospital, College of Stomatology, Shanghai Jiao Tong University School of Medicine , Shanghai, China .

Objectives: Some polymorphisms of the interleukin-16 (IL-16) gene are associated with various cancers. To resolve inconsistencies in published data, we performed a meta-analysis of studies of IL-16 polymorphisms and cancer risk.

Materials And Methods: Seven eligible studies pooling 1678 cases and 1937 controls were quantitatively analyzed to evaluate three IL-16 polymorphisms (rs4778889, rs4072111, rs11556218) and cancer risk. Hardy-Weinberg equilibrium (HWE) for controls was evaluated by goodness-of-fit chi-squared tests. Odds ratios (ORs) and their 95% confidence intervals (CIs) were calculated for each genetic model and allelic comparison. Data were pooled using fixed- or random-effects models depending on heterogeneity across studies.

Results: Our meta-analysis demonstrated that the IL-16 polymorphism rs11556218 was significantly associated with increased susceptibility to cancer in several models, including allelic contrast (OR=1.307; 95% CI, 1.108-1.541), heterozygote contrast (OR=1.650; 95% CI, 1.424-1.911), and dominant model (OR=1.605; 95% CI, 1.391-1.845). The result remained consistent after adjustment for age and gender. No significant association was found between IL-16 polymorphisms rs4778889 rs4072111 and cancer risk.

Conclusions: The rs11556218 T/G polymorphism of the IL-16 gene was significantly associated with elevated cancer risk in Asian populations. Our results warrant larger, better-designed studies, including a greater ethnic variety.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1089/gtmb.2013.0386DOI Listing
March 2014

Synthesis of nanostructured materials by using metal-cyanide coordination polymers and their lithium storage properties.

Nanoscale 2013 Nov 26;5(22):11087-93. Epub 2013 Sep 26.

College of Material Science and Engineering and Key Laboratory for Intelligent Nano Materials and Devices of Ministry of Education, Nanjing University of Aeronautics and Astronautics, Nanjing, China.

Herein, we demonstrate a novel and simple two-step process for preparing LiCoO2 nanocrystals by using a Prussian blue analogue Co3[Co(CN)6]2 as a precursor. The resultant LiCoO2 nanoparticles possess single crystalline nature and good uniformity with an average size of ca. 360 nm. The unique nanostructure of LiCoO2 provides relatively shorter Li(+) diffusion pathways, thus facilitating the fast kinetics of electrochemical reactions. As a consequence, high reversible capacity, excellent cycling stability and rate capability are achieved with these nanocrystals as cathodes for lithium storage. The LiCoO2 nanocrystals deliver specific capacities of 154.5, 135.8, 119, and 100.3 mA h g(-1) at 0.2, 0.4, 1, and 2 C rates, respectively. Even at a high current density of 4 C, a reversible capacity of 87 mA h g(-1) could be maintained. Importantly, a capacity retention of 83.4% after 100 cycles is achieved at a constant discharge rate of 1 C. Furthermore, owing to facile control of the morphology and size of Prussian blue analogues by varying process parameters, as well as the tailored design of multi-component metal-cyanide hybrid coordination polymers, with which we have successfully prepared porous [email protected] nanocubes, one of the potential anode materials for lithium-ion batteries, such a simple and scalable approach could also be applied to the synthesis of other nanomaterials for energy storage devices.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1039/c3nr03289bDOI Listing
November 2013

Association between 5-HT2A receptor polymorphisms and risk of obstructive sleep apnea and hypopnea syndrome: a systematic review and meta-analysis.

Gene 2013 Nov 26;530(2):287-94. Epub 2013 Aug 26.

Department of Oral and Craniofacial Science, Ninth People's Hospital, College of Stomatology, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology, Shanghai 200011, China.

Obstructive sleep apnea and hypopnea syndrome (OSAHS) is a common disorder with several predisposing factors, which may include genetic causes. Studies of the association of susceptibility to and severity of OSAHS with the polymorphisms of the 5-HTR 2A/2C genes have had low statistical power and have yielded inconsistent results. To clarify the association we perform a meta-analysis that combines the genotyping data from all eligible published studies. We quantitatively analyzed five publications, which included a pool of 633 cases and 512 controls, addressing the 5-HT receptor polymorphism and the risk of OSAHS. Hardy-Weinberg equilibrium (HWE) and the minor allele frequency of genetic frequency distributions for the controls were calculated. Differences in the distribution of genotypes between cases and controls were compared by odds ratios (ORs) with their 95% confidence intervals (CIs). For each genetic model, data were pooled using fixed- or random-effects models, depending on the inter-publication heterogeneity. Our results from pooled data showed that individuals carrying the 5-HTR 2A -1438G/A AA genotype had an increased risk of OSAHS (OR=3.69, 95% CI=1.92-7.08) compared with those carrying the GG genotype. Significant results were also reached under a recessive model (OR=3.16, 95% CI=2.33-4.30, p<0.01). However, the results declined to an OR of 2.16 (95% CI=0.9-5.21) in a homozygote model when the studies were restricted to HWE. No statistically significant results concerning an association of the 102C/T polymorphism of the 5-HTR 2A gene with OSAHS were reached (p>0.05 for each genetic model). This meta-analysis suggested that the 5-HTR 2A -1438G/A genotype might modulate an elevated risk of OSAHS. No association of the 5-HTR 2A 102C/T genotype polymorphism with OSAHS was established. However, some publications exhibited HWE bias, which might influence the reliability of pooled data. Further studies in this field, using larger samples, better designs and additional ethnicities, are warranted.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.gene.2013.08.012DOI Listing
November 2013

Porous nitrogen-doped carbon nanotubes derived from tubular polypyrrole for energy-storage applications.

Chemistry 2013 Sep 23;19(37):12306-12. Epub 2013 Jul 23.

College of Materials Science & Engineering and Key Laboratory for Intelligent Nano Materials and Devices of the Ministry of Education, Nanjing University of Aeronautics and Astronautics, Nanjing, 210016 (P.R. China), Fax: (+86) 025-52112626.

Porous nitrogen-doped carbon nanotubes (PNCNTs) with a high specific surface area (1765 m(2)  g(-1)) and a large pore volume (1.28 cm(3)  g(-1)) have been synthesized from a tubular polypyrrole (T-PPY). The inner diameter and wall thickness of the PNCNTs are about 55 nm and 22 nm, respectively. This material shows extremely promising properties for both supercapacitors and for encapsulating sulfur as a superior cathode material for high-performance lithium-sulfur (Li-S) batteries. At a current density of 0.5 A g(-1), PNCNT presents a high specific capacitance of 210 F g(-1), as well as excellent cycling stability at a current density of 2 A g(-1). When the S/PNCNT composite was tested as the cathode material for Li-S batteries, the initial discharge capacity was 1341 mA h g(-1) at a current rate of 1 C and, even after 50 cycles at the same rate, the high reversible capacity was retained at 933 mA h g(-1). The promising electrochemical energy-storage performance of the PNCNTs can be attributed to their excellent conductivity, large surface area, nitrogen doping, and unique pore-size distribution.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/chem.201301352DOI Listing
September 2013

Bone-anchored maxillary expansion and bilateral interoral mandibular distraction osteogenesis in adult with severe obstructive sleep apnea syndrome.

J Craniofac Surg 2013 May;24(3):949-52

Center of Craniofacial Orthodontics, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology, Shanghai, China.

Severe obstructive sleep apnea syndrome (OSAS) threatens patients' lives. To solve ventilation problem, snoring, and avoid another orthognathic surgery for mandibular advancement, bone-anchored rapid maxillary expansion and bilateral interoral mandibular distraction osteogenesis were tried on a 20-year-old Chinese male patient with severe skeletal class II malocclusion and OSAS.The patient had polysomnography (apnea-hypopnea index 54.2), body mass index measurement (19.7 kg/m), and cephalometry before the treatment. Bone-anchored rapid maxillary expansion was performed for the correction of maxillary transverse and minor sagittal deficiency and the improvement of nasal airflow by decreasing nasal resistance. Bilateral interoral mandibular distraction osteogenesis was operated to lengthen the small, retruded mandible by 15 mm. Orthodontic treatment after the maxillary expansion and mandibular distraction osteogenesis can help obtain stable occlusion.The Epworth Sleepiness Scale, a questionnaire for temporomandibular joint, cephalometric analysis, polysomnography, acoustic rhinometry, and multislice spiral computed tomography were performed to evaluate changes from the treatment. All the results showed that the patient had a significantly alleviated OSAS. In addition, an acceptable occlusion was also obtained.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/SCS.0b013e318286883bDOI Listing
May 2013

Optimizing conditions of polysaccharide extraction from Shiitake mushroom using response surface methodology and its regulating lipid metabolism.

Carbohydr Polym 2013 Jun 15;95(2):644-8. Epub 2013 Mar 15.

Department of Oral & Cranio-maxillofacial Science, Shanghai Ninth People's Hospital, College of Stomatology, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology, Shanghai 200011, China.

Process conditions (extraction time, extraction temperature, water/solid ratio and incubation time) of Shiitake mushroom polysaccharides (SMP) were optimized by conducting experiments at three different levels using the response surface method (RSM). A second-order polynomial response surface equation was developed indicating the effect of variables on polysaccharides yield. Contour maps generated using the response surface equation showed that all the experimental variables significantly affected the yield. The effect of SMP on oxidative damage in mice fed by high cholesterol diet (HCD) was done in vivo. Results showed that SMP can decreased serum total cholesterol (TC), triglyceride (TG), low density lipoprotein (LDL-c) levels, and increased high density lipoprotein (HDL-c) levels in HCD mice. Treatment with SMP reduced blood, liver lipid peroxidation level and increased antioxidant enzymes activities. Thus it can be concluded that SMP can improve lipid metabolism and decreased oxidative damage in HCD mice.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.carbpol.2013.03.035DOI Listing
June 2013

Encapsulating sulfur into hierarchically ordered porous carbon as a high-performance cathode for lithium-sulfur batteries.

Chemistry 2013 Jan 23;19(3):1013-9. Epub 2012 Nov 23.

College of Materials Science and Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, PR China.

A three-dimensional (3D) hierarchical carbon-sulfur nanocomposite that is useful as a high-performance cathode for rechargeable lithium-sulfur batteries is reported. The 3D hierarchically ordered porous carbon (HOPC) with mesoporous walls and interconnected macropores was prepared by in situ self-assembly of colloidal polymer and silica spheres with sucrose as the carbon source. The obtained porous carbon possesses a large specific surface area and pore volume with narrow mesopore size distribution, and acts as a host and conducting framework to contain highly dispersed elemental sulfur. Electrochemical tests reveal that the HOPC/S nanocomposite with well-defined nanostructure delivers a high initial specific capacity up to 1193 mAh g(-1) and a stable capacity of 884 mAh g(-1) after 50 cycles at 0.1 C. In addition, the HOPC/S nanocomposite exhibits high reversible capacity at high rates. The excellent electrochemical performance is attributed exclusively to the beneficial integration of the mesopores for the electrochemical reaction and macropores for ion transport. The mesoporous walls of the HOPC act as solvent-restricted reactors for the redox reaction of sulfur and aid in suppressing the diffusion of polysulfide species into the electrolyte. The "open" ordered interconnected macropores and windows facilitate transportation of electrolyte and solvated lithium ions during the charge/discharge process. These results show that nanostructured carbon with hierarchical pore distribution could be a promising scaffold for encapsulating sulfur to approach high specific capacity and energy density with long cycling performance.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/chem.201202127DOI Listing
January 2013

Three-dimensional coherent titania-mesoporous carbon nanocomposite and its lithium-ion storage properties.

ACS Appl Mater Interfaces 2012 Jun 4;4(6):2985-92. Epub 2012 Jun 4.

College of Material Science & Engineering, Nanjing University of Aeronautics and Astronautics , Nanjing, 210016, People's Republic of China.

Mesoporous, micro/nanosized TiO2/C composites with uniformly dispersed TiO2 nanoparticles embedded in a carbon matrix have been rationally designed and synthesized. In brief, TiO2 precursor was infiltrated into the channels of surface-oxidized mesoporous carbon (CMK-3) by means of electrostatic interaction, followed by in situ hydrolysis and growth of TiO2 nanocrystallites, resulting in ultrafine TiO2 nanoparticle confined inside the channels of mesopores carbon. After chemical lithiation and post-annealing, TiO2 nanoparticles were transformed in situ into Li4Ti5O12 to form highly conductivity mesoporous Li4Ti5O12/C composite, as confirmed by scanning electron microscope (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Raman spectroscopy, and nitrogen sorption isotherms. By combining high electronic conductivity, open mesoporosity, and nanosized active material, coherent mesoporous TiO2/C and Li4Ti5O12/C nanocomposites demonstrated high rate capability and good cycling properties.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/am300357bDOI Listing
June 2012

[Selection and application of oral appliance on patients with obstructive sleep apnea hypopnea syndrome].

Zhonghua Er Bi Yan Hou Tou Jing Wai Ke Za Zhi 2012 Feb;47(2):169-72

View Article and Find Full Text PDF

Download full-text PDF

Source
February 2012

[Effects of maxillary protraction on craniofacial structures and upper airway dimensions in skeletal Class III malocclusions].

Shanghai Kou Qiang Yi Xue 2009 Jun;18(3):229-33

Department of Oral and Maxillofacial Surgery, Ninth People's Hospital, College of Stomatology, Shanghai Jiao Tong University School of Medicine, Shanghai 200011, China.

Purpose: To evaluate the effect of maxillary protraction on upper airway dimensions in skeletal Class III malocclusions and to investigate the relationship between changes in craniofacial morphology and upper airway dimensions.

Methods: 22 patients who had maxillary retrognathism confirmed by cervical vertebral maturation and treated with face mask protraction. Pre- and post-treatment cephalometric radiographs were analyzed with SAS8.2 software package for paired t test and correlation analysis.

Results: The dimensions of PNS-ad1,PNS-ad2,PSP-SPPW, P-MPW increased significantly (P<0.01), Tb-TPPW decreased significantly (P<0.05). The change of V-LPW was not significant (P>0.05).Correlation was found between changes of PNS-Ba and PNS-ad1, PNS-ad2,V-LPW (P<0.05);changes of Hy-H1 and P-MPW,V-LPW (P<0.05);changes of Hy-H0 and V-LPW (P<0.05). No correlation was found between other pharyngeal measurements and investigated craniofacial variables(P>0.05).

Conclusions: Maxillary protraction can affect the upper airway structures. In addition, variables on craniofacial morphology are relative with upper airway dimensions.
View Article and Find Full Text PDF

Download full-text PDF

Source
June 2009
-->