Minimizing interfacial energy losses in inverted perovskite solar cells by a dipolar stereochemical 2D perovskite interface

Inverted perovskite solar cells(PSCs) have attracted broad research and industrial interest owing to their suppressed hysteresis,cost-effectiveness,and easy-fabrication.However,the issue of non-radiative recombination losses at the n-type interface between the perovskite and fullerene has impeded further improvement of photovoltaic performance.Here,we modify the n-type interface of FAPbI_(3) perovskite films by constructing a stereochemical two-dimensional(2D) perovskite interlayer,in which the organic cations comprise both pyridine and ammonium groups.The pyridine N donor can create stable bonding with the surface-uncoordinated Pb on the perovskite,thereby passivating the shallow-level defects and enhancing the air stability of the film.Furthermore,the pyridine N donor also offers a positive polar interface to decrease the surface work function of the perovskite film,enabling n-type modification.Ultimately,we employ a p-i-n photovoltaic(PV) device with the positive dipole interlayer at perovskite/fullerene contact and achieve remarkable photoelectric conversion efficiency(PCE) of 22.0%.

Residual alkali-evoked cross-linked polymer layer for anti-air-sensitivity LiNi_(0.89)Co_(0.06)Mn_(0.05)O_(2)cathode

High-energy density lithium-ion batteries(LIBs)with layered high-nickel oxide cathodes(LiNi_(x)Co_(y)Mn_(1-x-y)O_(2),x≥0.8)show great promise in consumer electronics and vehicular applications.However,LiNi_(x)Co_(y)Mn_(1-x-y)O_(2)faces challenges related to capacity decay caused by residual alkalis owing to high sensitivity to air.To address this issue,we propose a hazardous substances upcycling method that fundamentally mitigates alkali content and concurrently induces the emergence of an anti-air-sensitive layer on the cathode surface.Through the neutralization of polyacrylic acid(PAA)with residual alkalis and then coupling it with 3-aminopropyl triethoxysilane(KH550),a stable and ion-conductive cross-linked polymer layer is in situ integrated into the LiNi_(0.89)Co_(0.06)Mn_(0.05)O_(2)(NCM)cathode.Our characterization and measurements demonstrate its effectiveness.The NCM material exhibits impressive cycling performance,retaining 88.4%of its capacity after 200 cycles at 5 C and achieving an extraordinary specific capacity of 170.0 mA h g^(-1) at 10 C.Importantly,this layer on the NCM efficiently suppresses unfavorable phase transitions,severe electrolyte degradation,and CO_(2)gas evolution,while maintaining commendable resistance to air exposure.This surface modification strategy shows widespread potential for creating air-stable LiNi_(x)Co_(y)Mn_(1-x-y)O_(2)cathodes,thereby advancing high-performance LIBs.

Fragmentation of brain apolipoprotein E(ApoE)and its relevance in late onset Alzheimer's disease

Late-onset Alzheimer's disease(LOAD)is the most common cause of dementia in the elderly.Polymorphism in apolipoprotein E(ApoE)gene(ε2,ε3,and ε4)is the greatest LOAD risk factor.The translation products are ApoE2,ApoE3,and ApoE4,respectively.ApoE fragments are present in senile plaques and neurofibillary tangles but their contributions to AD pathogenesis are not clear.

Nano-capillary induced assemble of quantum dots on perovskite grain boundaries for efficient and stable perovskite solar cells

In recent years, perovskite solar cells(PSCs) have propelled into the limelight owing to rapid development of efficiency;however, the abundant defects at the perovskite grain boundaries result in unwanted energy loss and structural degradation. Here, the grain boundaries of perovskite polycrystalline films have been found to act as nanocapillaries for capturing perovskite quantum dots(PQDs), which enable the conformal assemble of PQDs at the top interspace between perovskite grains. The existence of PQDs passivated the surface defects, optimized the interfacial band alignments, and ultimately improved the power conversion efficiency from 19.27% to 22.47% in inverted PSCs. Our findings open up the possibility of selective assembly and structural modulation of the perovskite nanostructures towards efficient and stable PSCs.

Waste to treasure:Reutilization of fluid catalytic cracking coke block as photothermal conversion material for water evaporation

This study aims to analyze the coking process and propose an effective method for the reutilization of fluid catalytic cracking(FCC)coke block.Herein,we analyzed the basic characteristics and chemical composition of FCC coke blocks.The results showed that the main components were carbon,oxygen,and aluminum,accounting for 60.8%,26.6%,and 11.5%,respectively.Under the conventional catalytic cracking reaction temperature from 500℃ to 600℃,the formation of the first aromatic hydrocarbon was particularly important for the formation of coke.The condensation of oil-gas-entrained catalyst particles and their heavy components was the physical cause of coking,while the dehydrogenation condensation reaction of oil-gas heavy components was the chemical factor.In addition,the membrane prepared by powdered coke had excellent photothermal conversion ability,which could be heated to more than 110℃ within 360 s under two fixed light intensities.The evaporation rate of photothermal water was 5.89 kg m^(2) h^(−1),which has great industrial application potential.These works provide a novel and effective method of separation membrane for the reutilization of FCC coke blocks.

Diel dynamics of multi-omics in elkhorn fern provide new insights into weak CAM photosynthesis

Crassulacean acid metabolism(CAM)has high water-use efficiency(WUE)and is widely recognized to have evolved from C3 photosynthesis.Different plant lineages have convergently evolved CAM,but the molecular mechanism that underlies C3-to-CAM evolution remains to be clarified.Platycerium bifurcatum(elkhorn fern)provides an opportunity to study the molecular changes underlying the transition from C3 to CAM photosynthesis because both modes of photosynthesis occur in this species,with sporotrophophyll leaves(SLs)and cover leaves(CLs)performing C3 and weak CAM photosynthesis,respectively.Here,we report that the physiological and biochemical attributes of CAM in weak CAM-performing CLs differed from those in strong CAM species.We investigated the diel dynamics of the metabolome,proteome,and transcriptome in these dimorphic leaves within the same genetic background and under identical environmental conditions.We found that multi-omic diel dynamics in P.bifurcatum exhibit both tissue and diel effects.Our analysis revealed temporal rewiring of biochemistry relevant to the energy-producing pathway(TCA cycle),CAM pathway,and stomatal movement in CLs compared with SLs.We also confirmed that PHOSPHOENOLPYRUVATE CARBOXYLASE KINASE(PPCK)exhibits convergence in gene expression among highly divergent CAM lineages.Gene regulatory network analysis identified candidate transcription factors regulating the CAM pathway and stomatal movement.Taken together,our results provide new insights into weak CAM photosynthesis and new avenues for CAM bioengineering.

Characteristics of Diesel/N-Butanol Blend on a Common Rail Diesel Engine with Exhaust Gas Recirculation

20%n-butanol is blended in diesel by volume(noted as D80B20)and experiment has been carried out to study the effect on the combustion and emission characteristics based on a common rail diesel engine with exhaust gas recirculation(EGR)system.The results reveal thatD80B20 has longer ignition delay,shorter combustion duration and higher maximumin-cylinder temperature than pure diesel(noted as D100).Further,the number concentration and volume concentration of ultrafine particles decrease significantly while NO_(X) emissions increase a little with the addition of n-butanol.When the exhaust gas is induced into cylinder,NO_(X) emissions significantly decrease and ultrafine particles emissions increase.The number geometric mean diameters and volume geometricmean diameters of ultrafine particles increase withEGR ratio.Compared toD100 without EGR,D80B20 with 20%EGR ratio can reduce both NO_(X) and ultrafine particles emissions at 0.14MPa BMEP and 0.56MPa BMEP.

Time-Series Field Phenotyping of Soybean Growth Analysis by Combining Multimodal Deep Learning and Dynamic Modeling

The rate of soybean canopy establishment largely determines photoperiodic sensitivity,subsequently influencing yield potential.However,assessing the rate of soybean canopy development in large-scale field breeding trials is both laborious and time-consuming.High-throughput phenotyping methods based on unmanned aerial vehicle(UAV)systems can be used to monitor and quantitatively describe the development of soybean canopies for different genotypes.In this study,high-resolution and time-series raw data from field soybean populations were collected using UAVs.

DEKR-SPrior:An Efficient Bottom-Up Keypoint Detection Model for Accurate Pod Phenotyping in Soybean

The pod and seed counts are important yield-related traits in soybean.High-precision soybean breeders face the major challenge of accurately phenotyping the number of pods and seeds in a high-throughput manner.Recent advances in artificial intelligence,especially deep learning(DL)models,have provided new avenues for high-throughput phenotyping of crop traits with increased precision.However,the available DL models are less effective for phenotyping pods that are densely packed and overlap in insitu soybean plants;thus,accurate phenotyping of the number of pods and seeds in soybean plant is an important challenge.To address this challenge,the present study proposed a bottom-up model,DEKR-SPrior(disentangled keypoint regression with structural prior),for insitu soybean pod phenotyping,which considers soybean pods and seeds analogous to human people and joints,respectively.In particular,we designed a novel structural prior(SPrior)module that utilizes cosine similarity to improve feature discrimination,which is important for differentiating closely located seeds from highly similar seeds.To further enhance the accuracy of pod location,we cropped full-sized images into smaller and high-resolution subimages for analysis.The results on our image datasets revealed that DEKR-SPrior outperformed multiple bottom-up models,viz.,Lightweight-Open Pose,OpenPose,HigherH R Net,and DEKR,reducing the mean absolute error from 25.81(in the original DEKR)to 21.11(in the DEKR-SPrior)in pod phenotyping.This paper demonstrated the great potential of DEKR-SPrior for plant phenotyping,and we hope that DEKR-SPrior will help future plant phenotyping.

石墨烯掺杂聚合物复合材料介电性能建模

基于界面极化理论提出了一个石墨烯掺杂聚合物复合材料的介电模型,描述了石墨烯对复合材料有效介电常数的影响。该模型解释了石墨烯纳米片与聚合物基体在界面层的相互作用,计算了界面层的局部介电常数和局部电场强度,并通过控制变量方式对模型内材料参数的影响进行了分析。与传统经验模型相比,提出的模型明确了分离上限距离、势垒高度、基体层电导率、石墨烯纳米片层尺寸等因素对有效介电常数的影响机制。对多类二元、三元介电复合材料体系的有效介电常数进行了预测,并与实验样品实测值、文献值进行对比,验证了所提出模型的有效性。

A mussel-inspired supramolecular hydrogel with robust tissue anchor for rapid hemostasis of arterial and visceral bleedings

In recent years,the developed hemostatic technologies are still difficult to be applied to the hemostasis of massive arterial and visceral hemorrhage,owing to their weak hemostatic function,inferior wet tissue adhesion,and low mechanical properties.Herein,a mussel-inspired supramolecular interaction-cross-linked hydrogel with robust mechanical property(308.47±29.20 kPa)and excellent hemostatic efficiency(96.5%±2.1%)was constructed as a hemostatic sealant.Typically,we combined chitosan(CS)with silk fibroin(SF)by cross-linking them through tannic acid(TA)to maintain the structural stability of the hydrogel,especially for wet tissue adhesion ability(shear adhesive strength=29.66±0.36 kPa).Compared with other materials reported previously,the obtained CS/TA/SF hydrogel yielded a lower amount of blood loss and shorter time to hemostasis in various arterial and visceral bleeding models,which could be ascribed to the synergistic effect of wound closure under wet state as well as intrinsic hemostatic activity of CS.As a superior hemostatic sealant,the unique hydrogel proposed in this work can be exploited to offer significant advantages in the acute wound and massive hemorrhage with the restrictive access of therapeutic moieties.

Fuzzy control decision-making framework adapted to the uncertainty environment of complex software system

As the system becomes more intelligent and embedded,the operating environment is gradually changed from closed,static,and controllable to more open,dynamic,and difficult to control.As a result,the design of complex software systems is faced with many challenges arising from the uncertainty of the environment(UoE).On the one hand,ignoring the UoE to manually describe requirements is not only a tough job,but it can also hinder the discovery of potential requirements;on the other hand,it is a challenge to integrate the representation of and reasoning of UoE into the process of modeling complex systems.Based on the analysis of the characteristics of complex systems engineering,this paper takes solving the UoE caused by stakeholders prefer-ences and complex environment context as the entry point and designs a fuzzy con-trol decision-making framework.Specifically,the framework contributes to the spiral of complex systems while solving the UoE by constructing a closed-loop intelligent sys-tem based on automatic data flow between information space and physical space for environment sensing,uncertainty analysis,requirements mining,fuzzy reasoning,deci-sion execution as well as feedback optimization.Finally,the framework is validated with a concrete example of an adaptive treadmill system based on the support tools developed.

Chinese guidelines for the application of colon cancer staging recognition systems based on artificial intelligence platforms (2021)

The incidence and mortality of colon cancer in China are increasing each year.At present,treatment selection for colon cancer patients mainly depends on imaging results,which require a large number of radiologists to interpret.In China,there is a shortage and uneven distribution of experienced radiologists,which leads to delays and bias in the evaluation of imaging data.Based on these considerations,the Colorectal Surgery Group of the Surgery Branch of the Chinese Medical Association in collaboration with experts at Beihang University has independently developed an artificial intelligence(AI)-based recognition system for the preoperative determination of colon cancer stage to partially replace the work of and relieve the pressure on radiologists.These guidelines aim to standardize the use of AI-based recognition systems in the preoperative staging of colon cancer and guide their clinical application.

Discovery of novel ursolic acid derivatives as effective antimicrobial agents through a ROS-mediated apoptosis mechanism

In response to the reduction of food production and economic losses caused by plant bacterial diseases, it is necessary to develop new, efficient, and green pesticides. Natural products are rich and sustainable source for the development of new pesticides due to their low toxicity, easy degradation, and eco-friendliness. In this study, we prepared three series of ursolic acid derivatives and assessed their antibacterial ability. Most target compounds exhibited outstanding antibacterial activities. Among them, the relative optimal EC50 values of Xanthomonas oryzae pv. oryzae and Xanthomonas axonopodis pv. citri were 2.23 (A17) and 1.39 (A16) μg·mL^(-1), respectively. The antimicrobial mechanism showed that compound A17 induced an excessive accumulation and production of reactive oxygen species in bacteria and damaged the cell membrane integrity to kill bacteria. More interestingly, the addition of low concentrations of exogenous hydrogen peroxide enhanced the antibacterial efficacy of compound A17 against Xanthomonas oryzae pv. oryzae. These entertaining results suggested that compound A17 induced an apparent apoptotic behavior in the tested bacteria. Overall, we developed the promising antimicrobial agents that destroyed the redox system of phytopathogenic bacteria, further demonstrating the unprecedented potential of ursolic acid for agricultural applications.

哈萨克斯坦的生物多样性保护及中哈合作的对策建议

哈萨克斯坦位于欧亚大陆腹地,地处丝绸之路经济带的重要位置。中国与哈萨克斯坦开展生物多样性保护合作,有助于解决地区生态环境问题和推动"一带一路"倡议的顺利实施。目前国内尚缺乏对哈萨克斯坦生物多样性及其保护状况的了解。本文在文献的基础上通过定量和定性分析方法,从地理环境特征、生物多样性状况、保护成效和需求等维度对哈萨克斯坦生物多样性及其保护的总体情况进行了分析。分析结果表明,哈萨克斯坦的生物多样性丰富,但也存在着较严重的丧失问题;哈萨克斯坦政府重视生物多样性保护,积极承担相关国际履约义务;在保护管理方面实行多级管理体制,并与社会经济发展需求相结合,取得了一定成效。

A Lamb wave quantification model for inclined cracks with experimental validation

This paper investigates the influence of crack orientation on damage quantification using Lamb wave in plate structures. Finite element simulation is performed to acquire Lamb wave signal responses for different configurations of crack orientations and crack lengths. Two Lamb wave features, namely the normalized amplitude and the phase change, are used as damage sensitive features to develop a crack size quantification model. A hypothesis based on the geometrical influence on signal features is proposed, and the crack size quantification model incorporating the orientation angle is established using the hypothesis. An index of Probability of Reliable Quantification(PRQ) is proposed to evaluate the performance of the model. The index can be used to determine the sizing risk in terms of probabilities. A realistic aluminum plate is used to obtain the experimental data using piezoelectric(PZT) wafer-type sensors around a center through crack. The experimental data are used to validate the overall method. Results indicate that the proposed model can yield reliable results for size quantification of inclined cracks.

Olfactory and gustatory dysfunctions of COVID-19 patients in China:A multicenter study

Introduction:With the spread of the epidemic worldwide,an increasing number of doctors abroad have observed the following atypical symptoms of coronavirus disease 2019(COVID-19):olfactory or taste disorders.Therefore,clarifying the incidence and clinical characteristics of olfactory and taste disorders in Chinese COVID-19 patients is of great significance and urgency.Materials and Methods:A retrospective study was conducted,which included 229 severe acute respiratory syndrome coronavirus 2 confirmed patients,through face-to-face interviews and telephone follow-up.Following the completion of questionnaires,the patients participating in the study,were categorized according to the degree of olfactory and taste disorders experienced,and the proportion of each clinical type of patient with olfactory and taste disorders and the time when symptoms appeared were recorded.Results:Among the 229 patients,31(13.54%)had olfactory dysfunction,and 44(19.21%)had gustatory dysfunction.For the patients with olfactory dysfunction,6(19.35%)developed severe disease and became critically ill.Olfactory dysfunction appeared before the other symptoms in 21.43%of cases.The proportion of females with olfactory and gustatory dysfunction was higher than that of males(P<0.001).Conclusions:The incidence of olfactory and gustatory dysfunction was much lower than that reported abroad;the prognosis of patients with olfactory dysfunction is relatively favorable;olfactory and gustatory dysfunction can be used as a sign for early screening;females are more prone to olfactory and gustatory dysfunction.

Advances in cycloaddition and hydroaddition reaction of α -(trifluoromethyl)styrenes without defluorination: An alternative approach to CF_(3) -containing compounds

α-(Trifluoromethyl)styrene and its derivatives have found wide applications in the fields of pharmaceuti-cals,agrochemicals,and advanced materials.They are also versatile trifluoromethyl-containing building blocks for the preparation of various trifluoromethyl-containing,fluorine-containing or nonfluorinated compounds.Recently,great efforts have been made to develop diverse reactions for rapidly accessing a wide range of valuable gem–difluoroalkenes and gem–difluoroalkylated compounds via defluorinative re-action or the defluorinative ipso-functionalization reaction ofα-(trifluoromethyl)styrenes,respectively.In contrast,α-(trifluoromethyl)styrenes remain notably underdeveloped with respect to their use in cycload-dition and hydroaddition reaction with retaining of three C–F bonds.This short review herein is aimed to summarize the recent progress on the cycloaddition and hydroaddition reaction including nucleophilic,radical and transition metal-catalyzed addition ofα-(trifluoromethyl)styrenes without accompanying de-fluorination.

Et_(3)N-Catalyzed Cycloaddition Reactions ofα-(Trifluoromethyl)styrenes with 2,2,2-Trifluorodiazoethane to Access Bis(trifluoromethyl)-Substituted Pyrazolines

A novel and practical method for the synthesis of 3,5-bis(trifluoromethyl)-4,5-dihydro-1H-pyrazoles by [3+2] cycloaddition reactions of α-(trifluoromethyl)styrenes with 2,2,2-trifluorodiazoethane (CF3CHN2) has been developed. The cyclization reaction proceeds smoothly in the presence of a catalytic amount of Et_(3)N, affording a variety of bis(trifluoromethyl)-substituted 2-pyrazolines in good to excellent yields. This method also exhibits a broad substrate scope and tolerates various functional groups.