期刊文献+
共找到33篇文章
< 1 2 >
每页显示 20 50 100
Fine mapping and characterization of a major QTL for grain length,QGl.cau-2D.1,that has pleiotropic effects in synthetic allohexaploid wheat
1
作者 Mingming Wang Jia Geng +8 位作者 Zhe zhang zihan zhang Lingfeng Miao Tian Ma Jiewen Xing Baoyun Li Qixin Sun Yufeng zhang Zhongfu Ni 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第9期2911-2922,共12页
Grain size is one of the determinants of grain yield,and identifying the genetic loci that control grain size will be helpful for increasing grain yield.In our previous study,a quantitative trait locus(QTL)for grain l... Grain size is one of the determinants of grain yield,and identifying the genetic loci that control grain size will be helpful for increasing grain yield.In our previous study,a quantitative trait locus(QTL)for grain length(GL),QGl.cau-2D.1,was identified from an F2 population developed from the cross between the natural(TAA10)and synthetic(XX329)allohexaploid wheat.In the present study,we mainly fine mapped and validated its genetic effects.To this end,multiple near-isogenic lines(NILs)were obtained through marker-assisted selection with TAA10 as the recurrent parent.The secondary populations derived from 25 heterozygous recombinants were used for fine mapping of QGl.cau-2D.1,and the allele from XX329 significantly increased GL,thousand-grain weight(TGW),total spikelet number per spike(TSN)and spike compactness(SC).Using NILs for XX329(2D+)and TAA10(2D−),we determined the genetic and pleiotropic effects of QGl.cau-2D.1.The target sequences were aligned with the wheat reference genome RefSeq v2.1 and spanned an~0.9 Mb genomic region.TraesCS2D03G0114900(ortholog of Os03g0594700)was predicted as the candidate gene based on whole-genome re-sequencing and expression analyses.In summary,the map-based cloning of QGl.cau-2D.1 will be useful for improving grain weight with enhanced GL and TSN. 展开更多
关键词 grain length total spikelet number per spike spike compactness near-isogenic lines QTL WHEAT
下载PDF
Calculating real-time surface deformation for large active surface radio antennas using a graph neural network
2
作者 zihan zhang Qian Ye +2 位作者 Li Fu Qinghui Liu Guoxiang Meng 《Astronomical Techniques and Instruments》 CSCD 2024年第5期267-274,共8页
This paper presents an innovative surrogate modeling method using a graph neural network to compensate for gravitational and thermal deformation in large radio telescopes.Traditionally,rapid compensation is feasible f... This paper presents an innovative surrogate modeling method using a graph neural network to compensate for gravitational and thermal deformation in large radio telescopes.Traditionally,rapid compensation is feasible for gravitational deformation but not for temperature-induced deformation.The introduction of this method facilitates real-time calculation of deformation caused both by gravity and temperature.Constructing the surrogate model involves two key steps.First,the gravitational and thermal loads are encoded,which facilitates more efficient learning for the neural network.This is followed by employing a graph neural network as an end-to-end model.This model effectively maps external loads to deformation while preserving the spatial correlations between nodes.Simulation results affirm that the proposed method can successfully estimate the surface deformation of the main reflector in real-time and can deliver results that are practically indistinguishable from those obtained using finite element analysis.We also compare the proposed surrogate model method with the out-of-focus holography method and yield similar results. 展开更多
关键词 Large radio telescope Surface deformation Surrogate model Graph neural network
下载PDF
Multiscale evolution mechanism of sandstone under wet-dry cycles of deionized water:From molecular scale to macroscopic scale 被引量:2
3
作者 Jie Meng Changdong Li +5 位作者 Jia-Qing Zhou zihan zhang Shengyi Yan Yahui zhang Dewei Huang Guihua Wang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第5期1171-1185,共15页
Water is the most abundant molecule found on the earth’s surface and is a key factor in multiscale rock destruction.However,given the fine-grained nature of rock and the complexity of its internal structure,the micro... Water is the most abundant molecule found on the earth’s surface and is a key factor in multiscale rock destruction.However,given the fine-grained nature of rock and the complexity of its internal structure,the microstructural evolution of rock under the action of water has not yet been elucidated in detail,and little is understood about the relationship between the rock structure and solideliquid unit.A variety of techniques were used in this study to track the mechanical properties,pore and crack characteristics,and mineral structure degradation characteristics of sandstone at different stages under the action of deionized water,and the evolution mechanisms of the microstructure were analyzed at the molecular scale.The results showed that during the watererock interaction process,water was adsorbed onto the surface of dolomite minerals and the hydrophilic surface of clay minerals,forming a high-density hydrogen bond network.However,different mineral surface structures had different water adsorption structures,resulting in the strain of the dense clay mineral aggregates under expansion action.Stress concentrated at crack tips under the capillary force of dolomite minerals(very weak dolomite dissolution).These effects resulted in a substantial increase in the number of small pores and enhancements in poreecrack connectivity,and the rock strength exhibited varying degrees of decline at different stages of wet-dry cycles.In general,the results of this paper will help to further elucidate the internal connections between molecular-scale and macroscale processes in rock science. 展开更多
关键词 Rock structure Watererock interaction Multiscale evolution Adsorption structure Hydrogen bond
下载PDF
Gradient carbonyl-iron/carbon-fiber reinforced composite metamaterial for ultra-broadband electromagnetic wave absorption by multi-scale integrated design 被引量:1
4
作者 Qian Zhou Tiantian Shi +7 位作者 Bei Xue Shengyue Gu Wei Ren Fang Ye Xiaomeng Fan Wenyan Duan zihan zhang Lifei Du 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第6期1198-1206,共9页
The demand of high-end electromagnetic wave absorbing materials puts forward higher requirements on comprehensive performances of small thickness,lightweight,broadband,and strong absorption.Herein,a novel multi-layer ... The demand of high-end electromagnetic wave absorbing materials puts forward higher requirements on comprehensive performances of small thickness,lightweight,broadband,and strong absorption.Herein,a novel multi-layer stepped metamaterial absorber with gradient electromagnetic properties is proposed.The complex permittivity and permeability of each layer are tailored via the proportion of carbonyliron and carbon-fiber dispersing into the epoxy resin.The proposed metamaterial is further optimized via adjusting the electromagnetic parameters and geometric sizes of each layer.Comparing with the four-layer composite with gradient electromagnetic properties which could only realize reflection loss(RL)of less than−6 dB in 2.0-40 GHz,the optimized stepped metamaterial with the same thickness and electromagnetic properties realizes less than−10 dB in the relevant frequency range.Additionally,the RL of less than−15 dB is achieved in the frequency range of 11.2-21.4 GHz and 28.5-40 GHz.The multiple electromagnetic wave absorption mechanism is discussed based on the experimental and simulation results,which is believed to be attributed to the synergy effect induced by multi-scale structures of the metamaterial.Therefore,combining multi-layer structures and periodic stepped structures into a novel gradient absorbing metamaterial would give new insights into designing microwave absorption devices for broadband electromagnetic protections. 展开更多
关键词 broadband absorption METAMATERIALS gradient impedance multi-scale synergic effect
下载PDF
First-principles study on the conventional superconductivity of N-doped fcc-LuH_(3) 被引量:1
5
作者 Zihao Huo Defang Duan +6 位作者 Tiancheng Ma zihan zhang Qiwen Jiang Decheng An Hao Song Fubo Tian Tian Cui 《Matter and Radiation at Extremes》 SCIE EI CSCD 2023年第3期65-71,共7页
Recently,room-temperature superconductivity has been reported in a nitrogen-doped lutetium hydride at near-ambient pressure[Dasenbrock-Gammon et al.,Nature 615,244(2023)].The superconducting properties might arise fro... Recently,room-temperature superconductivity has been reported in a nitrogen-doped lutetium hydride at near-ambient pressure[Dasenbrock-Gammon et al.,Nature 615,244(2023)].The superconducting properties might arise from Fm3m-LuH_(3)−δNε.Here,we systematically study the phase diagram of Lu–N–H at 1 GPa using first-principles calculations,and we do not find any thermodynamically stable ternary compounds.In addition,we calculate the dynamic stability and superconducting properties of N-doped Fm3m-LuH_(3) using the virtual crystal approximation(VCA)and the supercell method.The R3m-Lu_(2)H_(5)N predicted using the supercell method could be dynamically stable at 50 GPa,with a T_(c) of 27 K.According to the VCA method,the highest T_(c) is 22 K,obtained with 1%N-doping at 30 GPa.Moreover,the doping of nitrogen atoms into Fm3m-LuH_(3) slightly enhances T_(c),but raises the dynamically stable pressure.Our theoretical results show that the T_(c) values of N-doped LuH_(3) estimated using the Allen–Dynes-modified McMillan equation are much lower than room temperature. 展开更多
关键词 SUPERCONDUCTIVITY DOPING HYDRIDE
下载PDF
Microwave ablation combined with transarterial chemoembolization containing doxorubicin hydrochloride liposome for treating primary and metastatic liver cancers
6
作者 Qin Shi zihan zhang +5 位作者 Wen zhang Jingqin Ma Minjie Yang Jianjun Luo Lingxiao Liu Zhiping Yan 《Journal of Interventional Medicine》 2023年第3期121-125,共5页
Aims:To determine the safety and efficacy of microwave ablation(MWA)and transarterial chemoembolization(TACE)with doxorubicin hydrochloride liposome(DHL)in patients with primary liver cancer(PLC)and metastatic liver c... Aims:To determine the safety and efficacy of microwave ablation(MWA)and transarterial chemoembolization(TACE)with doxorubicin hydrochloride liposome(DHL)in patients with primary liver cancer(PLC)and metastatic liver cancer(MLC).Materials and methods:The medical records of patients with primary or metastatic liver cancer who underwent MWA combined with TACE containing DHL from March 2019 to March 2022 were collected and analyzed.Treatment-related adverse events(AEs)were recorded.Local tumor response was evaluated according to the modified RECIST criteria.Local tumor progression-free survival(LTPFS)and overall survival(OS)were calculated using the Kaplan-Meier method.Results:Altogether,96 patients with liver cancer were included(PLC,n=45;MLC,n=51).Forty(41.7%)patients experienced AEs during treatment,and eight(8.3%)patients developed grade 3 AEs.Compared to before treatment,the serum total bilirubin level and neutrophil to lymphocyte ratio significantly increased after treatment.The median LTPFS was 14.5 months in patients with PLC and 10.7 months in patients with MLC.The median OS was not reached in patients with PLC or MLC.The 1-month and 3-month disease control rates reached more than 80%in both groups.Conclusion:MWA combined with TACE with DHL may be a safe and effective method for the treatment of liver cancer. 展开更多
关键词 Liver cancer Doxorubicin hydrochloride liposome Transarterial chemoembolization Microwave ablation
下载PDF
The Shaping of Spatial Morphology by Water Systems in Traditional Villages in Southern Hunan, China and Its Mechanism of Action
7
作者 Yang Xu Wenlong Zhou zihan zhang 《World Journal of Engineering and Technology》 2023年第2期389-407,共19页
The abundant water resources, rainy climate and dense water network had deeply influenced the formation and development of traditional villages in the southern Hunan region of China. This paper was adopted b... The abundant water resources, rainy climate and dense water network had deeply influenced the formation and development of traditional villages in the southern Hunan region of China. This paper was adopted buffer zone analysis, categorical statistical analysis, vectorization analysis and data literature analysis, studied the shaping of traditional village site selection, plane form and internal spatial structure by water systems in southern Hunan, China, and the mechanism of their effects. The results showed that: 1) The shaping ability and mechanism of the traditional village water system in Xiangnan area on spatial morphology was mainly based on the function of the water system. 2) The layout and spatial morphology of traditional villages were deeply affected by the width, area and form of water systems in Xiangnan area. 3) Traditional villages gave more consideration to water systems with large watershed areas in site selection. 4) Water systems with small watershed areas generally had a greater impact on the internal structure of traditional villages. 展开更多
关键词 Ancient Villages of China Site Selection Two-Dimensional Planar Forms Street Structure
下载PDF
高固含量磺酸型水性聚氨酯的制备与性能 被引量:9
8
作者 候婧辉 张子涵 +1 位作者 马一飞 柴春鹏 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2020年第1期152-158,共7页
以异佛尔酮二异氰酸酯(IPDI)、聚(1,6-己二醇/新戊二醇-己二酸)(PHNA)、1,4-丁二醇(BDO)、乙二胺基乙磺酸钠(AAS)的水溶液(50%)为主要原料,三乙胺(TEA)为中和剂,利用2种乳化方法和不同的AAS用量制备了一系列的磺酸型水性聚氨酯乳液,并... 以异佛尔酮二异氰酸酯(IPDI)、聚(1,6-己二醇/新戊二醇-己二酸)(PHNA)、1,4-丁二醇(BDO)、乙二胺基乙磺酸钠(AAS)的水溶液(50%)为主要原料,三乙胺(TEA)为中和剂,利用2种乳化方法和不同的AAS用量制备了一系列的磺酸型水性聚氨酯乳液,并对乳液和胶膜的性能进行了测试。结果表明,与直接法相比,乳液分散法可以得到更高固含量的乳液;当AAS含量为2.2%时,乳液固含量能达到60%以上;乳液的透射电镜图像表明,乳液分散法可以对乳液粒径进行良好的设计与控制;乳液分散法引入了具有更小粒径和更多硬段的粒子,物理交联点增加,胶膜变得更致密;AAS含量为2.2%时,乳液分散法得到的胶膜吸水率为33.71%,拉伸强度为9.90 MPa,断裂伸长率为1262%,与直接法相比,胶膜吸水率降低66.24%,拉伸强度提高0.61 MPa,断裂伸长率降低110%。 展开更多
关键词 水性聚氨酯 高固含量 磺酸型 乳液分散法
下载PDF
Adjusting energy level alignment between HTL and CsPbI_(2)Br to improve solar cell efficiency 被引量:4
9
作者 zihan zhang Jia Li +5 位作者 Zhimin Fang Haipeng Xie Yongbo Yuan Chuantian Zuo Liming Ding Bin Yang 《Journal of Semiconductors》 EI CAS CSCD 2021年第3期11-13,共3页
Lead halide perovskites are at the forefront of optoelectronic materials due to their high absorption coefficient,tunable bandgap,long carrier diffusion length,and small exciton binding energy[1−3],yielding high-perfo... Lead halide perovskites are at the forefront of optoelectronic materials due to their high absorption coefficient,tunable bandgap,long carrier diffusion length,and small exciton binding energy[1−3],yielding high-performance optoelectronic devices. 展开更多
关键词 OPTOELECTRONIC TUNABLE ALIGNMENT
下载PDF
High T_(c) Superconductivity in Heavy Rare Earth Hydrides 被引量:3
10
作者 Hao Song zihan zhang +3 位作者 Tian Cui Chris JPickard Vladimir ZKresin Defang Duan 《Chinese Physics Letters》 SCIE CAS CSCD 2021年第10期31-36,共6页
Sulfur and lanthanum hydrides under compression display superconducting states with high observed critical temperatures.It has been recently demonstrated that carbonaceous sulfur hydride displays room temperature supe... Sulfur and lanthanum hydrides under compression display superconducting states with high observed critical temperatures.It has been recently demonstrated that carbonaceous sulfur hydride displays room temperature superconductivity.However,this phenomenon has been observed only at very high pressure.Here,we theoretically search for superconductors with very high critical temperatures,but at much lower pressures.We describe two of such sodalite-type clathrate hydrides,YbH6 and LuH6.These hydrides are metastable and are predicted to superconduct with T_(c)~145 K at 70 GPa and T_(c)~273 K at 100 GPa,respectively.This striking result is a consequence of the strong interrelationship between the f states present at the Fermi level,structural stability,and the final T_(c) value.For example,TmH6,with unfilled 4f orbitals,is stable at 50 GPa,but has a relatively low value of T_(c) of 25 K.The YbH6 and LuH6 compounds,with their filled f-shells,exhibit prominent phonon"softening",which leads to a strong electron-phonon coupling,and as a result,an increase in T_(c). 展开更多
关键词 SOFTENING FILLED RARE
下载PDF
Percutaneous microwave ablation combined with simultaneous transarterial chemoembolization for hepatocellular carcinoma with macrovascular invasion or extrahepatic metastases 被引量:4
11
作者 Mengfei Wu Shanshan Gao +6 位作者 Huadan Song zihan zhang Zhiyuan Zheng Zhiping Yan Xiaolin Wang Jianhua Wang Lingxiao Liu 《Journal of Interventional Medicine》 2019年第2期55-59,共5页
Objective:To evaluate the safety and efficacy of percutaneous microwave ablation(MWA)combined with simultaneous transarterial chemoembolization(TACE)in patients with hepatocellular carcinoma(HCC)patients with microvas... Objective:To evaluate the safety and efficacy of percutaneous microwave ablation(MWA)combined with simultaneous transarterial chemoembolization(TACE)in patients with hepatocellular carcinoma(HCC)patients with microvascular invasion(MVI)or extrahepatic metastases(EHM).Methods:Between August 2012 and April 2017,101 patients with MVI/EHM of HCC underwent percutaneous MWA combined with simultaneous TACE at our center.The clinical data were collected and analyzed for survival and prognostic factors.Results:The mean follow-up time was 23.6±14.7 months.One patient had grade 3 complications,and the median overall survival was 12.0 months(95%confidence interval 9.7-14.3).Multivariate analysis showed that ChildPugh class,serum alpha-fetoprotein level,and Eastern Cooperative Oncology Group performance status were independent factors of survival.Conclusion:Our results suggest that percutaneous MWA combined with simultaneous TACE is a safe and effective treatment for HCC with MVI/EHM. 展开更多
关键词 HEPATOCELLULAR CARCINOMA Combination therapy Microwave ablation SURVIVAL
下载PDF
Novel rubidium polyfluorides with F_(3), F_(4), and F_(5) species
12
作者 Ziyue Lin Hongyu Yu +4 位作者 Hao Song zihan zhang Tianxiao Liang Mingyang Du Defang Duan 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第6期414-418,共5页
Pressure has an important effect on chemical bonds and their chemical properties. The atypical compounds NaCl_(3) and CsF_(3) are predicted to be stable at high pressure and show unique physical and chemical propertie... Pressure has an important effect on chemical bonds and their chemical properties. The atypical compounds NaCl_(3) and CsF_(3) are predicted to be stable at high pressure and show unique physical and chemical properties. By using ab initio random structure searching and density functional theory calculations, we predicted multiple thermodynamically stable atypical compounds, which are RbF_(2), RbF_(3), RbF_(4), and RbF_(5) in the pressure range of 0–300 GPa. In these stable compounds, homonuclear bondings of F_(3), F_(4), and F_(5) species are easily formed. The electron structure calculation showed that except for Fd-3 m phase of RbF_(2), these stable compounds are insulators and F 5 p orbitals play an important role in the Fermi level. It is interesting that the compounds RbF_(5) could be stable at nearly ambient pressure and 0 K which will stimulate experimental studies in the future. 展开更多
关键词 high pressure crystal structure electron properties chemical bonds
下载PDF
从BRDF到BPDF:遥感反演基础模型的演进初探
13
作者 尚可 晏磊 +8 位作者 张飞舟 褚君浩 杨彬 刘思远 Kevin TANSEY 贾秀萍 Oleg DUBOVIK 张子晗 李飞 《中国科学:信息科学》 CSCD 北大核心 2024年第8期2001-2020,共20页
光的本质是横波电磁波矢量,以双向反射分布函数BRDF (bidirectional reflectance distribution function)为基础模型的标量遥感体系只利用植被反射光的整体强度信息,无法进一步区分反射辐射蕴含的叶表、叶内和冠层结构信息;在标量遥感... 光的本质是横波电磁波矢量,以双向反射分布函数BRDF (bidirectional reflectance distribution function)为基础模型的标量遥感体系只利用植被反射光的整体强度信息,无法进一步区分反射辐射蕴含的叶表、叶内和冠层结构信息;在标量遥感基础上考虑垂直于电磁波传播方向的二维偏振矢量特性(强度+方向)就能深化为矢量遥感体系,从而有望精确刻画反射光中蕴含的多种信息,提升植被参数反演精度.刻画偏振反射空间分布的双向偏振分布函数BPDF目前存在精度低、泛化性差等问题,因此进一步探索矢量遥感基础理论,构建通用性强的植被矢量遥感基础模型具有迫切的现实需求.本文旨在利用光子与植被元素的相互作用构建通用性较强的植被BPDF物理模型.首先基于光子–植被元素相互作用的光谱不变原理,提出基于方向逃逸概率的植被BPDF物理模型基础形式,并基于植被单次反射的辐射传输理论推导模型解析表达;随后通过考虑叶片散射随干物质含量的变化,提出光谱不变原理优化表达并推导模型通用表达式;最后分别利用三维矢量辐射传输模型和多尺度实测数据实现模型的正演直接验证和间接验证.结果表明,本文构建的BPDF物理模型的解析表达和通用表达在不同植被场景下,对偏振反射率的正演均方根误差可达0.001以内,与矢量辐射传输模型正演结果在半球空间内具有很强一致性,在多尺度实测数据也简洁验证了模型关系的稳定性,模型R2普遍高于0.9.相比于现存植被偏振反射模型,本文构建的模型兼具物理机理、简洁形式、可接受的参数化方案、较高精度和较强泛化能力,对浓密植被具备通用性,为在BRDF一维标量遥感的基础上进一步考虑BPDF二维偏振特性从而形成矢量遥感体系这一转变过程提供了理论基础和探索性方案. 展开更多
关键词 植被 BPDF 矢量遥感 物理模型 偏振
原文传递
A near-infrared fluorescent probe for visualizing transformation pathway of Cys/Hcy and H2S and its applications in living system
14
作者 Yudi Cheng Xiao Wang +5 位作者 Jiao Chen zihan zhang Jiadong Ou Mengyao She Fulin Chen Jianli Li 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第5期296-301,共6页
Sulfydryl-contained(-SH)substances including hydrogen sulfide(H_(2)S),cysteine(Cys),homocysteine(Hcy)and glutathione(GSH)play crucial roles in living systems,and their variations are closely associated with various di... Sulfydryl-contained(-SH)substances including hydrogen sulfide(H_(2)S),cysteine(Cys),homocysteine(Hcy)and glutathione(GSH)play crucial roles in living systems,and their variations are closely associated with various diseases.Herein,we developed a near-infrared intramolecular charge transfer(ICT)based fluorescent probe Y-NBD,achieving detection of Cys/Hcy and H_(2)S with different fluorescent signals(green-red for Cys/Hcy,red for H_(2)S),large Stokes shifts(∼100/105nm or 191 nm)and high signal-background-ratio,but not responding to GSH.Y-NBD was successfully applied to image exogenous/endogenous Cys/Hcy and H_(2)S in various living cancer cells(HeLa,A549,and HepG2)and in zebrafish.It not only visualized the transformation pathway of several thiols in HepG2 cells but also verified that the intestine is the main site for the activation and metabolism of Y-NBD in zebrafish,as well as realized to evaluate the degree of drug-induced liver injury.This work provides a promising tool for imaging Cys/Hcy and H_(2)S in living systems and shows great potency in evaluating drug-induced liver injury and its treatment. 展开更多
关键词 Fluorescent probe NEAR-INFRARED Hydrogen sulfide Cysteine/homocysteine Large Stokes shift Dicyanoisophorone Drug-induced liver injury
原文传递
Coping with the concurrent heatwaves and ozone extremes in China under a warming climate
15
作者 Mengmeng Li Xin Huang +9 位作者 Dan Yan Shiyi Lai zihan zhang Lei Zhu Yuting Lu Xinyi Jiang Nan Wang Tijian Wang Yu Song Aijun Ding 《Science Bulletin》 SCIE EI CAS CSCD 2024年第18期2938-2947,共10页
Intensive human activity has brought about unprecedented climate and environmental crises, in which concurrent heatwaves and ozone extremes pose the most serious threats. However, a limited understanding of the compre... Intensive human activity has brought about unprecedented climate and environmental crises, in which concurrent heatwaves and ozone extremes pose the most serious threats. However, a limited understanding of the comprehensive mechanism hinders our ability to mitigate such compound events, especially in densely populated regions like China. Here, based on field observations and climate-chemistry coupled modelling, we elucidate the linkage between human activities and the climate system in heatrelated ozone pollution. In China, we have observed that both the frequency and intensity of heatwaves have almost tripled since the beginning of this century. Moreover, these heatwaves are becoming more common in urban clusters with serious ozone pollution. Persistent heatwaves during the extremely hot and dry summers of 2013 and 2022 accelerated photochemical ozone production by boosting anthropogenic and biogenic emissions, and aggravated ozone accumulation by suppressing dry deposition due to water-stressed vegetation, leading to a more than 30% increase in ozone pollution in China's urban areas. The sensitivity of ozone to heat is demonstrated to be substantially modulated by anthropogenic emissions, and China's clean air policy may have altered the relationship between ozone and temperature. Climate model projections further highlight that the high-emission climate-socioeconomic scenario tends to intensify the concurrent heat and ozone extremes in the next century. Our results underscore that the implementation of a strict emission strategy will significantly reduce the co-occurrence of heatwaves and ozone extremes, achieving climate and environmental co-benefits. 展开更多
关键词 HEATWAVE OZONE Biogenic emission Dry deposition Ozone-temperature sensitivity
原文传递
Ring-Opening Copolymerization of Biorenewable -Caprolactone with trans-Hexahydro-(4,5)-benzofuranone toward Closed-Loop Recyclable Copolyesters and Their Application as Pressure- Sensitive Adhesives
16
作者 Haining Niu Liying Wang +3 位作者 zihan zhang Yalei Liu Yong Shen Zhibo Li 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2024年第17期2035-2042,共8页
Copolymerization as an efficient strategy can provide an opportunity to create new closed-loop recyclable polymeric materials with tailored properties that are generally inaccessible to the individual homopolymers.In ... Copolymerization as an efficient strategy can provide an opportunity to create new closed-loop recyclable polymeric materials with tailored properties that are generally inaccessible to the individual homopolymers.In this contribution,the bulk ring-opening copolymerization of bio-renewable-caprolactone and trans-hexahydro-(4,5)-benzofuranone was achieved to produce closed-loop recyclable copolyesters by using an organobase/urea binary catalyst at room temperature.The obtained copolyesters exhibited composition-dependent thermal properties.Remarkably,the obtained copolyesters were able to depolymerize back to recover the corresponding monomers under mild conditions. 展开更多
关键词 Recyclable polymers Ring-opening polymerization COPOLYMERIZATION Pressure-sensitive adhesives Aliphatic polyesters
原文传递
High Curie temperature and perfect spin filtering effect in a single layer Ga_(2)O_(3)magnetic tunnel junction
17
作者 zihan zhang Xinchen Ji +3 位作者 Jing Ning Dong Wang Yue Hao Jincheng zhang 《Science China Materials》 SCIE EI CAS CSCD 2024年第10期3262-3271,共10页
The electronic structure and magnetic properties of single layer Ga_(2)O_(3)in the presence of Ga and O vacancies are studied by first principles method based on density functional theory.The results show that the int... The electronic structure and magnetic properties of single layer Ga_(2)O_(3)in the presence of Ga and O vacancies are studied by first principles method based on density functional theory.The results show that the introduction of Ga vacancy(VGa)leads to a non-zero magnetic moment in singlelayer two-dimensional(2D)Ga_(2)O_(3),while VO does not.We find that Ga vacancies in two different symmetric positions can lead to spin polarized ground states.Notably,when the VGa ratio is greater than 1/16(indicating one Ga vacancy per 16 Ga atoms),single-layer 2D Ga_(2)O_(3)exhibits semi-metallic properties and its spin polarization reaches 100%at the Fermi level.Calculations of these two Ga vacancy systems also indicate a potential long-range ferromagnetic order at a high Curie temperature(355.8 K).Finally,a single layer 2D Ga_(2)O_(3)with high GaI vacancy(VGaI)ratio can be used as the ferromagnetic layer to obtain the magnetic tunnel junction(MTJ)with high spin filtering effect at the Fermi level.Ga vacant Ga_(2)O_(3)/MgO/Ga vacant Ga_(2)O_(3)MTJ exhibits excellent spin-filtering effect(with 100%spin polarization)and a giant tunneling magneto resistance(TMR)ratio(up to 1.12×10^(3)%).The results of this paper show that the MTJ based on two-dimensional Ga_(2)O_(3)with room temperature ferromagnetism exhibits reliable performance,showing the possibility of potential applications in spintronics. 展开更多
关键词 two-dimensional Ga_(2)O_(3) spin electronics room temperature ferromagnetism MTJ
原文传递
Ternary superconducting hydrides stabilized via Th and Ce elements at mild pressures
18
作者 Qiwen Jiang zihan zhang +5 位作者 Hao Song Yanbin Ma Yuanhui Sun Maosheng Miao Tian Cui Defang Duan 《Fundamental Research》 CAS CSCD 2024年第3期550-556,共7页
The discovery of covalent H_(3)S and clathrate structure LaH_(10) with excellent superconducting critical temperatures at high pressures has facilitated a multitude of research on compressed hydrides.However,their sup... The discovery of covalent H_(3)S and clathrate structure LaH_(10) with excellent superconducting critical temperatures at high pressures has facilitated a multitude of research on compressed hydrides.However,their superconducting pressures are too high(generally above 150 GPa),thereby hindering their application.In addition,making room-temperature superconductivity close to ambient pressure in hydrogen-based superconductors is challenging.In this work,we calculated the chemically“pre-compressed”Be-H by heavy metals Th and Ce to stabilize the superconducting phase near ambient pressure.An unprecedented ThBeH_(8)(CeBeH_(8))with a“fluorite-type”structure was predicted to be thermodynamically stable above 69 GPa(76 GPa),yielding a T_(c) of 113 K(28 K)decompressed to 7 GPa(13 GPa)by solving the anisotropic Migdal–Eliashberg equations.Be-H vibrations play a vital role in electron–phonon coupling and structural stability of these ternary hydrides.Our results will guide further experiments toward synthesizing ternary hydride superconductors at mild pressures. 展开更多
关键词 High pressure Hydrides SUPERCONDUCTIVITY Ab initio calculations Electron-phononcoupling
原文传递
Framework on low-carbon retrofit of rural residential buildings in arid areas of northwest China:A case study of Turpan residential buildings 被引量:6
19
作者 Junkang Song Wanjiang Wang +3 位作者 Pingan Ni Hanjie Zheng zihan zhang Yihuan Zhou 《Building Simulation》 SCIE EI CSCD 2023年第2期279-297,共19页
At present,buildings in arid and hot regions are facing severe challenges of indoor comfort improvement and carbon emission reduction,especially in rural areas.Multi-objective optimization could be an effective tool f... At present,buildings in arid and hot regions are facing severe challenges of indoor comfort improvement and carbon emission reduction,especially in rural areas.Multi-objective optimization could be an effective tool for tackling the aforementioned challenges.Therefore,this paper proposes a life-cycle optimization framework considering thermal comfort,which is beneficial to promoting residents’motivation for low-carbon retrofit in arid climate regions.First,in response to the above problems,three objective functions are specified in the framework,which are global warming potential(GWP),life cycle cost(LCC),and thermal discomfort hours(TDH).To improve the optimization efficiency,this research uses Deep Neural Networks(DNN)combined with NSGA-II to construct a high-precision prediction model(meta-model for optimization)based on the energy consumption simulation database formed by the orthogonal multi-dimensional design parameters.The accuracy index of the modified model is R2>0.99,cv(RMSE)≤1%,and NMBE≤0.2%,which gets rid of the dilemma of low prediction accuracy of traditional machine learning models.In the scheme comparison and selection stage,the TOPSIS based on two empowerment methods is applied to meet different design tendencies,where the entropy-based method can avoid the interference of subjective preference and significantly improve the objectivity and scientific nature of decision analysis.Additionally,sensitivity analysis is conducted on the variables,which supports guidance for practitioners to carry out the low-carbon design.Finally,the multi-objective optimization analysis for a farmhouse in Turpan is taken as a case study to evaluate the performance of the framework.The results show that the framework could significantly improve the building performance,with 60.8%,52.5%,and 14.2%reduction in GWP,LCC,and TDH,respectively. 展开更多
关键词 life cycle assessment arid regions deep neural networks entropy-based TOPSIS method multi-criteria optimization
原文传递
CRITICAL PROCESSES AND MAJOR FACTORS THAT DRIVE NITROGEN TRANSPORT FROM FARMLAND TO SURFACE WATER BODIES 被引量:1
20
作者 Wenchao LI Wen XU +8 位作者 Gaofei YIN Xulin zhang zihan zhang Bin XI Qiuliang LEI Limei ZHAI Qiang zhang Linzhang YANG Hongbin LIU 《Frontiers of Agricultural Science and Engineering》 CSCD 2023年第4期541-552,共12页
Agricultural non-point source pollution is increasingly an important issue affecting surface water quality.Currently,the majority of the studies on nitrogen loss have focused on the agricultural field scale,however,th... Agricultural non-point source pollution is increasingly an important issue affecting surface water quality.Currently,the majority of the studies on nitrogen loss have focused on the agricultural field scale,however,the response of surface water quality at the watershed scale into the nitrogen loss at the field scale is poorly understood.The present study systematically reviewed the critical processes and major factors that nitrogen transport from farm fields to surface water bodies.The critical processes of farmland nitrogen entering surface water bodies involve the processes of nitrogen transport from farmland to ditches and the transformation processes of nitrogen during migration in ditches/rivers.Nitrogen transport from farmland to ditches is one of the prerequisites and critical processes for farmland nitrogen transport to surface water bodies.The transformation of nitrogen forms in ditches/rivers is an intermediate process in the migration of nitrogen from farmland to surface water bodies.Nitrogen loss from farmland is related to soil storage and exogenous inputs.Therefore,nitrogen input management should not only consider the current input,but also the contribution of soil storage due to the historical surpluses.Ditches/rivers have a strong retention capacity for nitrogen,which will significantly affect the process of farmland nitrogen entering surface water bodies.The factors affecting nitrogen transformation in river/ditches can be placed in four categories:(1)factors affecting hydraulic retention time,(2)factors affecting contact area,(3)factors affecting biological activity,and(4)forms and amount of nitrogen loading to river/ditches.Ditch systems are more biologically(including plants and microbes)active than rivers with biological factors having a greater influence on nitrogen transformation.When developing pollution prevention and control strategies,ecological ditches can be constructed to increase biological activity and reduce the amount of surplus nitrogen entering the water body.The present research should be valuable for the evaluation of environment impacts of nitrogen loss and the non-point source pollution control. 展开更多
关键词 NITROGEN loss from soil TRANSFORMATION farm field scale watershed scale
原文传递
上一页 1 2 下一页 到第
使用帮助 返回顶部