Simulation design of P–I–N-type all-perovskite solar cells with high efficiency

According to the good charge transporting property of perovskite, we design and simulate a p–i–n-type all-perovskite solar cell by using one-dimensional device simulator. The perovskite charge transporting layers and the perovskite absorber constitute the all-perovskite cell. By modulating the cell parameters, such as layer thickness values, doping concentrations and energy bands of n-, i-, and p-type perovskite layers, the all-perovskite solar cell obtains a high power conversion efficiency of 25.84%. The band matched cell shows appreciably improved performance with widen absorption spectrum and lowered recombination rate, so weobtain a high J_（sc） of 32.47 m A/cm^2. The small series resistance of the all-perovskite solar cell also benefits the high J_（sc）. The simulation provides a novel thought of designing perovskite solar cells with simple producing process, low production cost and high efficient structure to solve the energy problem.

D-Type Anti-Ferromagnetic Ground State in Ca_2Mn_2O_5

We study the electronic and magnetic properties of an oxygen-deficient perovskite Ca2Mn2O5 based on the first principle calculations. The calculations show that the ground state of Ca2Mn2O5 is a D-type anti-ferromagnetic structure with the anti-ferromagnetic spin coupling along the c-direction. The corresponding electronic structure of the D-type state is investigated, and the results display that Ca2Mn2O5 is an insulator with an indirect energy gap of -2.08eV. By the partiM density-of-state analysis, the valence band maximum is mainly contributed to by the 0-213 orbitMs and the conduction band minimum is contributed to by the 0-213 and Mn-3d orbitals. Due to the Coulomb repulsion interaction between electrons, the density of state of Mn-3d is pulled to -6--4.5eV.

Species recognition and the divergences in the chemical and ultrasonic signals between two coexisting Rattus species

The ability to recognize and differentiate between conspecifics and heterospecifics as well as their signals is critical for the coexistence of closely related species.In the genus Rattus,species are morphologically similar and multiple species often coexist.Here,we investigated the interspecific recognition and signal differentiation of two sympatric rat species,the brown rat(Rattus norvegicus,RN)and the Asian house rat(Rattus tanezumi,RT).In a two-way choice test,both RN and RT females showed a preference for conspecific male rats to heterospecific ones.RT females showed a significant preference for accessible urine of males of same species to those of other species,but not for the inaccessi-ble urine.On the other hand,there were significant differences in the structural characteristics of the ultrasonic vocalization emitted by males of these two rat species.Sodium dodecyl sulphate-polyacrylamide gel electrophoresis(SDS-PAGE)and isoelectric focusing electrophoresis unveiled that major urinary proteins(MUPs)in voided urine were more highly expressed in RN males versus RT males.The interspecific dif-ferences of urinary volatile compounds were also discussed.In conclusion,female rats had the ability to distinguish between males of either species.

Weakening CO poisoning over size-and support-dependent Pt_(n)/X-graphene catalyst(X=C,B,N,n=1-6,13)

CO poisoning is one of the obstacles for platinum catalysts toward the electro-catalysis process for proton exchange membrane fuel cell(PEMFC)or direct methanol fuel cell(DMFC).Herein,we aim to weaken the CO poisoning on Pt by varying the cluster sizes and supports via doping graphene with B and N based on DFT+D3 calculations.

南祁连盆地木里坳陷中侏罗统烃源岩原始有机碳含量恢复及与微孔隙演化的相关性

泥页岩有机质碳含量(TOC)是页岩油气评价的重要参数之一。然而,受有机质热演化生排烃影响,利用现今TOC评价与预测页岩油气资源时会出现一定的偏差。因此,进行烃源岩原始有机碳恢复对油气资源评价具有重要意义。木里坳陷位于南祁连盆地东北部,陆相中侏罗统广泛分布。中侏罗统为一套湖泊—三角洲相沉积的细粒碎屑岩,发育多套厚层富有机质暗色泥页岩,生烃潜力巨大。该层段内油气资源丰富,页岩有机质从低成熟到高成熟阶段均有分布,为原始有机碳含量的恢复提供了必要条件。以木里坳陷中侏罗统富有机质页岩为研究对象,利用岩石热解数据,采用物质平衡法有机碳恢复模型,对中侏罗统页岩原始有机碳含量进行了恢复。结果表明,中侏罗统页岩原始TOC含量与现今TOC含量的比值介于1.04~1.62之间,且随着热演化程度增高,比值变大。现今TOC含量与有机质孔隙发育之间没有必然的联系,然而,原始TOC含量与现今TOC含量之间的比值可以间接判断页岩有机质微孔隙发育情况。木里坳陷侏罗系页岩有机质类型以Ⅱ型和Ⅲ型为主,热演化参数(T_(max))大于440℃时,烃类转化率和排烃率都大于40%。相比样品矿物(石英和黏土矿物)含量、T_(max)参数和现今TOC含量,原始TOC含量与页岩兰氏体积拟合性更好,结合热解参数T_(max),可以更好地判断页岩油气的吸附能力。因此,开展木里坳陷中侏罗统烃源岩原始有机碳含量恢复的研究,可以为木里坳陷烃源岩评价提供理论基础;同时对木里坳陷油气资源勘探提供新的思路。