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排序方式: 共有1439条查询结果,搜索用时 15 毫秒
61.
Helen Hejin Park Rachel Heasley Leizhi Sun Vera Steinmann Rafael Jaramillo Katy Hartman Rupak Chakraborty Prasert Sinsermsuksakul Danny Chua Tonio Buonassisi Roy G. Gordon 《Progress in Photovoltaics: Research and Applications》2015,23(7):901-908
Thin‐film solar cells consisting of earth‐abundant and non‐toxic materials were made from pulsed chemical vapor deposition (pulsed‐CVD) of SnS as the p‐type absorber layer and atomic layer deposition (ALD) of Zn(O,S) as the n‐type buffer layer. The effects of deposition temperature and annealing conditions of the SnS absorber layer were studied for solar cells with a structure of Mo/SnS/Zn(O,S)/ZnO/ITO. Solar cells were further optimized by varying the stoichiometry of Zn(O,S) and the annealing conditions of SnS. Post‐deposition annealing in pure hydrogen sulfide improved crystallinity and increased the carrier mobility by one order of magnitude, and a power conversion efficiency up to 2.9% was achieved. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
62.
Elastomeric Chlorosulfonated polyethylene (Hypalon®) and thermoplastic Polypropylene (PP) based thermoplastic vulcanizates (TPVs) were prepared in presence of different doses of compatibilizer, maleic anhydride grafted PP (PP‐g‐MA) by employing dynamic vulcanization technique. The effect of incorporation in different proportions of compatibilizer on mechanical, spectral, morphological, thermal, and rheological properties of such TPVs was studied and the same were compared to that of virgin PP and amongst themselves. The mechanical analysis of the prepared TPVs exhibited significant improvements in stress at 25% modulus, ultimate tensile strength (UTS), and hardness values. FTIR studies revealed that a chemical interaction had taken place between Hypalon® and functionalized compatibilizer during the process of dynamic vulcanization which led to an enhancement of interfacial adhesion between them. The two‐phase morphologies were clearly observed by scanning electron microscopic studies. The Tg values of Hypalon® was modified in the TPVs as exhibited by differential scanning calorimetric studies. TGA studies indicated the increase in thermal stability of all TPVs with respect to the elastomeric Hypalon®. Rheological properties showed that the compatibilizer reduces the melt viscosity of TPVs and thus facilitates the processibility of such TPVs. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40312. 相似文献
63.
Liquid polycarbosilane (LPCS) derived hard coatings of silicon carbide (SiC) were deposited on Inconel alloy at three different moderately high temperatures by chemical vapour deposition. The deposited films were characterized by X-ray diffractometry and Field emission scanning electron microscopy. Liquid PCS yielded a mixture of α-SiC and β-SiC during decomposition having uniform round-shaped particles of dimension around 200–300 nm without extensive cracking and few discrete shaped particles were also found to form at higher temperature (i.e. 1100 °C and 1200 °C) deposited films. The coated samples showed substantial increment in hardness and fracture toughness as compared to the uncoated sample. The fracture toughness (KIC) values of the deposited films were in the range of 6.7–10.7 MPa(m)1/2. The tribological properties and hardness of the films were also found to vary with deposition temperature. The scratch tracks of the films revealed that brittle failures occurred in all SiC coated substrates. 相似文献
64.
Steven He Rajdeep Chakraborty Shoba Ranganathan 《International journal of molecular sciences》2022,23(3)
Oral cancer is the most common form of head and neck squamous cell carcinoma (HNSCC) and most frequently presents as oral squamous cell carcinoma (OSCC), which is associated with an alarmingly high mortality rate. Internationally, a plethora of research to further our understanding of the molecular pathways related to oral cancer is performed. This research is of value for early diagnosis, prognosis, and the investigation of new drugs that can ameliorate the harmful effects of oral cancer and provide optimal patient outcomes with minimal long-term complications. Two pathways on which the progression of OSCC depends on are those of proliferation and apoptosis, which overlap at many junctions. Herein, we aim to review these pathways and factors related to OSCC progression. Publicly available search engines, PubMed and Google Scholar, were used with the following keywords to identify relevant literature: oral cancer, proliferation, proliferation factors, genes, mutations, and tumor suppressor. We anticipate that the use of information provided through this review will further progress translational cancer research work in the field of oral cancer. 相似文献
65.
Dibakar Sarkar Dr. Ipsita Chakraborty Marcello Condorelli Baijayanti Ghosh Thorben Mass Dr. Markus Weingarth Dr. Atin K Mandal Prof. Carmelo La Rosa Dr. Vivekanandan Subramanian Dr. Anirban Bhunia 《ChemMedChem》2020,15(3):293-301
The three GxxxG repeating motifs from the C-terminal region of β-amyloid (Aβ) peptide play a significant role in regulating the aggregation kinetics of the peptide. Mutation of these glycine residues to leucine greatly accelerates the fibrillation process but generates a varied toxicity profile. Using an array of biophysical techniques, we demonstrated the uniqueness of the composite glycine residues in these structural repeats. We used solvent relaxation NMR spectroscopy to investigate the role played by the surrounding water molecules in determining the corresponding aggregation pathway. Notably, the conformational changes induced by Gly33 and Gly37 mutations result in significantly decreased toxicity in a neuronal cell line. Our results indicate that G33xxxG37 is the primary motif responsible for Aβ neurotoxicity, hence providing a direct structure–function correlation. Targeting this motif, therefore, can be a promising strategy to prevent neuronal cell death associated with Alzheimer's and other related diseases, such as type II diabetes and Parkinson's. 相似文献
66.
Banani Ray Chowdhury Runu Chakraborty Utpal Ray Chaudhuri 《Journal of food engineering》2007,80(4):1171-1175
Data for the cell growth of Pediococcus acidilactici H during the fermentative production of bacteriocin, pediocin AcH (taken from a previous study) was modeled by two sigmoidal functions, modified Gompertz and Logistic. Results showed that the models could adequately account for the cell growth up to the growth phase, but failed to account for the stationary and death phase. 相似文献
67.
Anoop K. Mukhopadhyay Keshaw D. Joshi Arjun Dey Riya Chakraborty Ashok K. Mandal Amit Rav Jiten Ghosh Sandip Bysakh Sampad K. Biswas Satish C. Gupta 《Ceramics International》2011,37(7):2365-2376
Shock recovered samples of a coarse grain (10 μm), high density (>99.9% theoretical) alumina from asymmetric impact tests conducted at 6.5 GPa (e.g. 3.2 times its Hugoniot Elastic Limit) in a single stage gas gun and characterized by X-ray diffractometry, scanning and field emission scanning electron microscopy, and transmission electron microscopy showed prolific presence of reduced crystallite size, higher average microstrain, grain localized micro/nano-scale deformations, micro-cleavages, grain-boundary microcracks, micro-wing crack formation, extensive shear induced deformations and fractures localized at grains, grain boundaries and triple grain junctions, grain localized entanglement of dislocations and their pile up impeded at grain boundaries. A new qualitative model based on micro-shear and micro-twist induced deformation and fracture in single and/or multiple planes in suitably oriented grain and/or grain assembly was developed to explain the experimentally observed damage evolution process. 相似文献
68.
Bamboo strips [10 cm × 1.5 cm × (1?1.5) mm] were treated with caustic solutions for 1 h at different concentrations e.g., 0, 10, 15, 20, and 25%. Bamboo strips reinforced polyester resin composites were fabricated by hand‐lay‐up technique using both alkali‐treated and untreated bamboo strips, using a room temperature curing system for the polyester resin. This study aims at the evaluation of the influence of caustic concentration on the mechanical properties of bamboo strips reinforced polyester resin composites at a constant 50% loading of reinforcement. Maximum improvement in property was achieved possibly with 20% of caustic treated strip reinforcements. Beyond 20%, there was degradation in all the strength properties because of failure in mechanical properties of the reinforcements itself. The effect of fiber loading variation upon mechanical properties was also studied. It was observed that superior mechanical properties were obtained with 60% filler loading. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献
69.
Poly(ethylene oxide) (PEO)/clay nanocomposites were prepared by a solution intercalation method using chloroform as a solvent. The nanocomposites were characterised by X-ray diffraction (XRD), differential scanning calorimetry (DSC), hot-stage polarized optical microscopy (POM), Fourier transform infrared spectroscopy (FT-IR), tensile analysis, dynamic mechanical analysis (DMA) characterisation techniques. Formation of nanocomposite was confirmed by X-ray diffraction (XRD) analysis. A decrease in PEO crystallinity in case of nanocomposite, was confirmed by a decrease in the heat of melting and spherulite size as indicated by DSC and POM studies, respectively. Improvement in tensile properties in all respect was observed for nanocomposites with optimum clay content (12.5 wt%). DMA studies indicate an increase in loss peak temperature and broadening of loss peak as a result of clay intercalation. 相似文献
70.