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971.
Dual Functional Electron‐Selective Contacts Based on Silicon Oxide/Magnesium: Tailoring Heterointerface Band Structures while Maintaining Surface Passivation 下载免费PDF全文
Hui Tong Zhenhai Yang Xixi Wang Zhaolang Liu Zhenxin Chen Xiaoxing Ke Manling Sui Jiang Tang Tianbao Yu Ziyi Ge Yuheng Zeng Pingqi Gao Jichun Ye 《Liver Transplantation》2018,8(16)
Silicon (Si)‐based dopant‐free heterojunction solar cells (SCs) featuring carrier‐selective contacts (CSCs) have attracted considerable interest due to the extreme simplifications in their device structure and manufacturing procedure. However, these SCs are limited by the unsatisfactory contact properties on both sides of the junction, and their efficiencies are not comparable with those of commercially available Si SCs. In this report, a high‐performance silicon‐oxide/magnesium (SiOx/Mg) electron‐selective contact (ESC) design is described. Combining an ultrathin SiOx and a low work function Mg layer, the novel ESC simultaneously yields low recombinative and resistive losses. In addition, deposition of Mg on SiOx relaxes the restriction on the threshold thickness of the SiOx for electron tunneling and therefore broadens the optimization space for rear‐sided passivation. Meanwhile, hole‐selective contact with boosted light harvesting and suppressed interfacial recombination is achieved by forming a fully conformal contact between the conducting poly(3,4‐ethylene dioxythiophene): poly(styrenesulfonate) (PEDOT: PSS) and periodic Si pyramid arrays. With the double‐sided carrier‐selective contact designs, PEDOT: PSS/Si/SiOx/Mg SCs with efficiency of 15% are finally obtained via a totally dopant‐free processing. Subsequent calculations further indicate a pathway for the improvement of these contacts toward an efficiency that is competitive with conventionally diffused pn junction SCs. 相似文献
972.
A Hybrid Electrolytes Design for Capacity‐Equivalent Dual‐Graphite Battery with Superior Long‐Term Cycle Life 下载免费PDF全文
Yu Qiao Kezhu Jiang Xiang Li Han Deng Yibo He Zhi Chang Shichao Wu Shaohua Guo Haoshen Zhou 《Liver Transplantation》2018,8(24)
Based on cation/anion graphite intercalation chemistry (GIC) processes, dual‐graphite batteries promise to be an energy storage device of high safety and low cost. However, few single electrolyte systems can simultaneously meet the requirements of both high oxidative stability during high voltage anion‐GIC on cathode and high reversibility upon cation‐GIC on anode. Thus, in order to rigidly remedy the irreversible capacity loss, excessive electrode materials need to be fabricated within full cell, resulting in an imbalance toward capacity‐dependent mass loading proportion between both electrodes. This work introduces a hybrid (dual‐organic) electrolytes design strategy into this promising technology. Segregated by a Nafion‐based separator, an ionic liquid electrolyte within the cathodic side can endure high operation potentials, while high Li‐GIC reversibility can be achieved in a superconcentrated ether‐based electrolyte on the anode side. On a mechanistic level, various cation‐GIC processes conducted in different electrolyte systems are clearly revealed and are summarized based on systematical characterizations. More importantly, after synergistically tuning the advantage and drawback of each electrolyte in this hybrid system, the dual‐graphite full cell assembled with capacity‐equivalent graphite‐based electrodes (1:1 mass loading) demonstrates superior long‐term cycling stability with ultrahigh capacity retention for over 3000 cycles. 相似文献
973.
Zhanghui Dong Jianhong Zhang Qingzhu Zhu Lifen Zhao Shuxiang Sui Zengshu Li Yanli Zhang Hu Wang Dongliang Tian Yankun Zhao 《Genes & genomics.》2018,40(3):305-314
Drought stress is one of the most important abiotic stresses. Cotton is classified as drought tolerant crop but the regulatory mechanism is unknown. MicroRNAs (miRNAs) have been implicated important roles in stress responses in many plants. However, the study of miRNAs in cotton responsive to drought stress is limited, especially in early-maturing cotton. In this study, we performed deep sequencing of small RNAs to identify known and novel miRNAs involved in the regulation of drought stress and understand the expression profile of miRNAs in early-maturing cotton. Three cotton small RNA libraries: non-stressed Shizao1 (early-maturing cotton variety) library (NSS), drought-stressed Shizao1 library (DSS) and non-stressed Jimian958 (medium-maturing cotton variety) library (NSJ) were constructed for deep sequencing. As a result, we identified a total of 64 known and 67 novel miRNAs in the 3 libraries and 88 of them were dramatically differentially expressed (greater than twofold) during drought stress. In addition, we found the expression of 41 miRNAs increased or reduced more than twofold in early-maturing cotton variety compared with that in medium-maturing cotton variety. Our results significantly increased the number of miRNAs in cotton and revealed for the first time the expression profile of miRNAs for early-maturing cotton. 相似文献
974.
Guanchao?Lan Shaohua?Jin Dongxu?Wang Jing?Li Zhiyan?Lu Baochao?Jing Lijie?LiEmail author 《Journal of molecular modeling》2018,24(7):186
The influences of the temperature and the BDNPA/BDNPF (A3) content on the mechanical properties of and the binding energies between hexanitrohexaazaisowurtzitane (HNIW) and cellulose acetate butyrate (CAB)/A3 were studied via molecular dynamics simulations. The morphology of HNIW in acetone was simulated using an attachment energy (AE) model to elucidate the HNIW surfaces that are present under real-world conditions. The simulation results were consistent with the experimentally derived ones, and they indicated that the exposed HNIW surfaces were (0 0 1), (1 1 0), and (1 1 ?1). The mechanical properties of CAB with different amounts of A3 were calculated at different temperatures, and the results showed that the amount of A3 was a stronger influence than the temperature on the mechanical properties. The binding energies between CAB/A3 and the exposed HNIW surfaces were calculated. Based on the binding energy and the area of each exposed surface, the weighted-average binding energy was calculated and then used instead of the total binding energy to evaluate the effect of the temperature and the A3 content on the binding energy. The average binding energy was found to be highest when the temperature was 313 K and the mass fraction of A3 was 0.15. 相似文献
975.
976.
Direct evidence for the localization of the steroid-binding site of the plasma sex steroid-binding protein (SBP or SHBG) at the interface between the subunits. 总被引:2,自引:0,他引:2 下载免费PDF全文
L. M. Sui W. Hughes A. J. Hoppe P. H. Ptra 《Protein science : a publication of the Protein Society》1996,5(12):2514-2520
Complete dissociation of dimeric plasma sex steroid-binding protein (SBP or SHBG) was obtained in 6 M urea at 10 degrees C. Removal of urea resulted in the refolding of monomers, followed by reformation of dimeric SBP, which migrates with the same mobility as the native protein. Dimerization does not require Ca+2 or steroid. Renatured monomers yield dimers with dissociation constants for 5 alpha-dihydrotesterone (DHT) and 17 beta-estradiol (E2) indistinguishable from those of native human SBP. This phenomenon was also demonstrated by mixing human and rabbit SBPs that, upon renaturation, form a hybrid dimer composed of one human subunit and one rabbit subunit. The hybrid binds both DHT and E2 in contrast to rSBP, which only binds the androgen. Therefore, we conclude that (1) docking of the two subunits creates an asymmetric steroid-binding site located at the interface between the subunits, and (2) only one face of the dimer defines the specificity for binding E2 by encompassing portion of a structural motif that recognizes the flat ring A of E2. The remaining portion, which recognizes the saturated ring A of DHT, is shared by both faces of the dimer. Because native monomers do not exist alone, the often-asked question of whether the SBP monomer binds steroid can be considered meaningless; steroid-binding activity is expressed only in the dimeric state. Finally, formation of the hybrid indicates that SBP dimerization represents a conserved event during the molecular evolution of SBP, suggesting that the structural elements responsible for dimerization will be homologous in SBPs from other species. 相似文献
977.
SincetheCenozoic,changesofmammalsintaxonomiccompositionanddistributionhavetakenplaceinChina,mainlyduetocollisionofplates,changesoftopographyandclimate.ThepaperdiscussessomeproblemsofecologyandbiogeographyinvolvingtheChneseCenozoicmammals,aftertherecognitionofthe18manunalagesbasedonnatureandmagnitudeofthefaunalchanges(Tongetal.,1995).BiogeOgraPhicProvincesandec0l0gyChinaisvastinterritoryandtheclimatebetweenthenorthernahds0uthernpartsdiffers'Thepresentmammaliandistributionindicatesdistinctpr… 相似文献
978.
Tonghai Dou Chaoneng Ji Shaohua Gu Fei Chen Jiaxi Xu Xin Ye Kang Ying Yi Xie Yumin Mao 《DNA sequence》2005,16(3):230-234
Rab GTPase proteins are a kind of small GTP-binding proteins, which functions mainly focus on regulating interacellular trafficking pathways during vesicular transport. To date, 60 distinct human RAB proteins have been identified. RAB18 gene is discovered from endothelial cells. Its function is considered as endosomes and plasma membrane recycling. Research indicates RAB18 may relate to inflammation and some kinds of tumor. Here we report a splice variant of RAB18, which is 2571 bp in length and has an open reading frame coding a predicted 235 amino-acids protein. RT-PCR shows that the cDNA has different expression pattern with RAB18 and is highly expressed in testis. 相似文献
979.
980.