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Grain dehydration rate is related to post-silking thermal time and ear characters in different maize hybrids

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Journal of Integrative Agriculture 2022年第4期21卷 964-976页

作者： SHI Wen-jun SHAO Hui SHA Ye SHI Rong SHI Dong-feng chen ya-chao BAN Xiang-ben MI Guo-hua The Key Lab of Plant–Soil Interaction Ministry of Education/National Academy of Agriculture Green Development/College of Resources and Environmental ScienceChina Agricultural UniversityBeijing 100193P.R.China

Mechanized grain harvest of maize becomes increasingly important with growing land plot size in Northeast China. Grain moisture is an important factor affecting the performance of mechanized grain harvest. However, it remains unclear what influences grain dehydration rate. In this study, maize grain dehydrating process was investigated in a two-year field experiment with five hybrids under two planting densities in 2017 and 2018. It was found that damaged-grain ratio was the main factor affecting mechanized harvest quality, and this ratio was positively correlated with grain moisture content at harvest(R^(2)=0.6372, P<0.01). To fulfill the national standard of <5% damaged-grain ratio for mechanized grain harvest, the optimal maize grain moisture content was 22.3%. From silking to physiological maturity, grain dehydrating process was mostly dependent on the thermal time(growing degree days, GDDs)(r=-0.9412, P<0.01). The average grain moisture content at physiological maturity was 29.4%. Thereafter, the linear relationship between GDDs and grain moisture still existed, but the correlation coefficient became smaller(r=-0.8267, P<0.01). At this stage, grain dehydrating process was greatly affected by genotypes. Grain dehydrated faster when a hybrid has a smaller husk area(r=0.6591, P<0.05), larger ear angle(r=-0.7582, P<0.05), longer ear peduncle(r=-0.9356, P<0.01) and finer ear(r=0.9369, P<0.01). These parameters can be used for breeders and farmers to select hybrids suitable for mechanized grain harvest.

关键词： maize grain moisture grain dehydrating grain damage mechanized harvest ear traits genotype

Association between heat and upper urinary tract stones morbidity and medical costs: A study in the subtropical humid climate zone

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Advances in Climate Change Research 2024年第4期15卷 717-724页

作者： chen-Lu yaNG Jun-Zhe BAO Peng BI ya-Dong ZHANG chao-Ming TAN Kai chen College of Public Health Zhengzhou UniversityZhengzhou 450001China School of Public Health The University of AdelaideAdelaide 5000Australia Department of Andrology The First Affliated Hospital of Sun Yat-sen UniversityGuangzhou 510080China Nanjing Social Insurance Management Center Nanjing 210008China Department of Environmental Health Sciences Yale UniversityNew Haven 06520USA yale Center on Climate Change and Health Yale UniversityNew Haven 06520USA

Urolithiasis is a heat-specific *** heat-related urolithiasis susceptibility subtypes,economic burden,and modifying factors could assist governments in targeting interventions to reduce the heat-related health risks of urolithiasis *** collected data on 23,492 patients with upper urinary tract stones(main subtypes of urolithiasis)from 2013 to 2017 in Nanjing,*** adopted generalized additive quasi-Poisson models to examine the associations between daily mean temperatures and morbidity of upper urinary tract stones,while generalized additive Gaussian models were used to explore the relationships between temperatures and log-transformed medical *** examined the modification effects of disease subtypes(kidney and ureteral calculus),sex,and age through stratified analyses and the modif-cation effects of other meteorological factors by introducing interaction terms in the *** found that short-term summer heat exposure has a statistically significant effect on ureteral calculus morbidity but not on kidney calculus *** ureter calculus,a 1℃ temperature increase was associated with a 4.36%(95%confidence interval[CI]:1.94%,6.83%)increase in daily hospitalization and a 5.44%(95%CI:2.71%,8.25%)increase in daily medical *** attributable fraction associated with heat(greater than the median value of daily mean temperature,26.8℃)was 7.85%(95%empirical confidence interval[eCI]:3.64%,11.44%)for hospitalization and 9.36%(95%eCI:4.91%,13.14%)for medical *** effects of heat on ureter calculus morbidity were significantly higher among the males and those with high sunshine duration than females and those with low sunshine ***-term summer heat exposure was associated with increased morbidity and medical costs of ureteral *** government organizations should take effective intervention measures,including community health education,to reduce the health hazards and economic losses caused by heat.

关键词： Heat Upper urinary tract stones Economic burden Modification effects

Strong electron correlation-induced Mott-insulating electrides of Ae_(5)X_(3)(Ae=Ca,Sr,and Ba;X=As and Sb)

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Matter and Radiation at Extremes 2024年第3期9卷 74-82页

作者： ya Xu Lu Zheng Yunkun Zhang Zhuangfei Zhang QianQian Wang Yuewen Zhang Liangchao chen chao Fang Biao Wan Huiyang Gou Key Laboratory of Material Physics of Ministry of Education School of Physics and Laboratory of Zhongyuan LightZhengzhou UniversityZhengzhou 450052China School of Mechanical and Equipment Engineering Hebei University of EngineeringHandan 056038China Center for High Pressure Science and Technology Advanced Research Beijing 100094China

The presence of interstitial electrons in electrides endows them with interesting attributes,such as low work function,high carrier concentration,and unique magnetic *** knowledge and understanding of electrides are thus of both scientific and technological ***,we employ first-principles calculations to investigate Mott-insulating Ae_(5)X_(3)(Ae=Ca,Sr,and Ba;X=As and Sb)electrides with Mn_(5)Si_(3)-type structure,in which half-filled interstitial electrons serve as ions and are *** Mott-insulating property is induced by strong electron correlation between the nearest interstitial electrons,resulting in spin splitting and a separation between occupied and unoccupied *** half-filled antiferromagnetic configuration and localization of the interstitial electrons are critical for the Mott-insulating properties of these *** with that in intermetallic electrides,the orbital hybridization between the half-filled interstitial electrons and the surrounding atoms is weak,leading to highly localized magnetic centers and pronounced correlation ***,the Mott-insulating electrides Ae_(5)X_(3)have very large indirect bandgaps(0.30 eV).In addition,high pressure is found to strengthen the strong correlation effects and enlarge the *** present results provide a deeper understanding of the formation mechanism of Mott-insulating electrides and provide guidance for the search for new strongly correlated electrides.

关键词： intermetallic filled occupied

粉末状芳香族聚酰亚胺金属复合结合剂的制备研究

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热固性树脂 2024年第2期39卷 42-47页

作者：马红磊彭进王园园张琳琪郭星宇陈亚超河南工业大学材料科学与工程学院河南郑州450001 郑州海科研磨工具有限公司河南郑州450100

为解决传统树脂结合剂耐热性不高及与低熔点金属温度匹配性差的问题,以2,2′-双[4-(4-氨基苯氧基)苯基]丙烷(BAPP)和均苯四甲酸酐(PMDA)为单体,通过两步合成法制备聚酰亚胺树脂(PI),通过调控反应参数发现加料顺序为先胺后酐,反应时间6 h... 详细信息

为解决传统树脂结合剂耐热性不高及与低熔点金属温度匹配性差的问题,以2,2′-双[4-(4-氨基苯氧基)苯基]丙烷(BAPP)和均苯四甲酸酐(PMDA)为单体,通过两步合成法制备聚酰亚胺树脂(PI),通过调控反应参数发现加料顺序为先胺后酐,反应时间6 h,单体PMDA与BAPP物质的量比为1.02∶1时,PI分子质量最佳,具有较好的力学性能(纯PI结合剂弯曲强度达95 MPa)和热稳定性(初始分解温度约510℃)。其与低熔点铜合金制备复合结合剂时,具有较好的成型温度匹配性和耐热性,当树脂体积分数为10%时,PI及聚酰胺酸复合结合剂的弯曲强度分别为532 MPa和540 MPa,综合性能较佳。

关键词：聚酰亚胺耐高温复合结合剂低熔点金属合金弯曲强度热稳定性

Fixed-Time Anti-Disturbance Average-Tracking for Multi-Agent Systems Without Velocity Measurements

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Journal of Systems Science & Complexity 2024年第3期37卷 985-1002页

作者： LI Yuling LIU chenglin ZHANG ya chen yangyang Key Laboratory of Advanced Process Control for Light Industry(Ministry of Education) Institute of AutomationJiangnan UniversityWuci 214122China School of Automation Southeast UniversityNanjing 210096China

In this paper,the authors tackle a fixed-time average-tracking problem for multi-agent systems which do not require velocity measurements and are affected by external mismatched and matched *** objective requires the considered agents with second-order dynamics to follow the average value of several time-varying reference signals,each of which is acquired by only one *** of all,the average value is estimated by using a novel distributed average estimator in a fixed ***,an original observer is created to provide estimated values in a fixed time for external mismatched and matched disturbances as well as unmeasured velocities of ***,the authors propose a novel fixed-time anti-disturbance average-tracking protocol with the aid of the observer and a sliding mode *** the end,the feasibility of theoretical analysis is illustrated by some simulation experiments.

关键词： Average-tracking control fixed-time algorithm fixed-time observer mismatched distur-bances multi-agent systems velocity measurements

Significant effect of ordered micro-domain on cell boundary phase distribution and demagnetization curve squareness of Sm_(2)Co_(17)-type magnet

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Rare Metals 2024年第4期43卷 1724-1735页

作者： Zhuang Liu Hai-chen Wu chao-Yue Zhang chao-Qun Zhu Guo-Xin chen Huan-Ming Lu Ren-Jie chen Aru yan CISRI&NIMTE Joint Innovation Center for Rare Earth Permanent Magnets Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo315201China University of Chinese Academy of Sciences Beijing100049China Analytical Center Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo315201China

Cu-rich cell boundary phase is difficult to precipitate evenly,resulting in a generally poor demagnetization curve squareness for Fe-rich Sm_(2)Co_(17)-type magnet,which is a key factor limiting the further improvement of magnetic energy *** this study,we report that nanoscale strip-like ordered micro-domains distributed in1:7H disordered matrix phase of the solid solution precursor is a new factor significantly affecting the precipitation and distribution of the cell boundary *** strip-like and continuous micro-twin structure with twin boundaries neatly perpendicular to the C-axis is observed after sintering *** solution treatment,sequential and long strip-like micro-twins gradually transform into disordered state along the basal plane,forming narrow disordered 1:7H(TbCu_(7)-type structure)phase between the separated strip-like ordered *** disordering transformation takes place via broken down of the long strip-like ordered micro-domains,which is accomplished by narrowing along the width direction followed by reduction of the ***,a new model revealing the effect of the ordered micro-domains on the formation of the cell boundary phase is *** boundaries enriched in Cu have already existed in the precursor with long strip-like ordered ***,the Cu-rich cell boundary phase acting as strong pinning centers cannot be precipitated homogeneously and distributed continuously after aging,resulting in a poor demagnetization curve squareness of Sm_(2)Co_(17)-type *** results indicate that significant broken down of the nanoscale ordered micro-domains in solution precursor is the key factor improving the distribution of cell boundary phase in Sm_(2)Co_(17)-type magnets.

关键词： Sm_(2)Co_(17) magnets Solution precursor Ordered micro-domains Disordering transformation Cellular structure

Chain Dynamics Heterogeneity in Plasticized Poly(vinyl butyral)(PVB) as Elucidated by Solid-State NMR

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Chinese Journal of Polymer Science 2024年第1期42卷 113-124,I0010页

作者： Jing Lv Xu chen Zi-Shuo Wu ya-Hui Li Wei chen National Synchrotron Radiation Laboratory Anhui Provincial Engineering Laboratory of Advanced Functional Polymer FilmCAS Key Laboratory of Soft Matter ChemistryUniversity of Scienceand Technology of ChinaHefei 230026China

The chain dynamics heterogeneity of the poly(vinyl butyral)(PVB) plasticized by triethylene glycol bis(2-ethylhexa noate)(TEG-EH) was investigated by various solid-state NMR *** plasticized PVB shows two domains in distinct molecular dynamics differences,namely,rigid and soft domains,where the latter is the plasticizer-rich *** time domain low field NMR was first used to investigate the dynamics heterogeneity of the plasticized PVB,and the results show the decreasing activated energy of components in the soft domain of plasticized PVB(E_a=20.2 kJ/mol) as compared with that of the pristine one(E_a=24.3 kJ/mol).Detailed dynamics heterogeneity was obtained by high-field NMR with site-specific *** quadrupole-echo ~2H-NMR was adopted to elucidate the dynamics heterogeneity of the vinyl alcohol(VA) units,where only the hydroxyl group of VA is *** ~1H-^(13)C WISE NMR spectra show that there is not much difference in the mobility of the VB unit in PVB with and without plasticizer,whereas the glass transition temperature differed by approximately 53℃.This is further supported by Torchia's T_1 relaxation *** origin of such an unusual phenomenon is attributed to the critical role of the remaining VA(~22%) in the soft domain,where the VA units locally aggregate through hydrogen ***,the existence of a mobility gradient in the VB unit has been ***,the mobility difference for VB with different stereo-geometry(meso or racemic conformation) is observed for the first *** indicates the importance of modulating the ratio of meso over racemic VB for controlling the macroscopic perfo rmance of PVB.

关键词： Poly(vinyl butyral) Dynamics heterogeneity Plasticizer Solid state NMR

Review on recent advances of inorganic electrode materials for potassium-ion batteries

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Tungsten 2024年第1期6卷 174-195页

作者： Jian-Zhen Xiong Ze-cheng yang Xin-Liang Guo Xi-Ying Wang chao Geng Zong-Fu Sun An-Yong Xiao Quan-chao Zhuang ya-Xin chen Zhi-cheng Ju School of Materials Science and Physics China University of Mining and TechnologyXuzhou 221116China

Rechargeable potassium-ion batteries(PIBs)have great potential in the application of electrochemical energy storage devices due to the low cost,the abundant resources and the low standard reduction potential of *** electrode materials are the key factors to determine the electrochemical performance of devices,relevant research is being carried out to build high-performance *** recent years,significant progress has been made in the study of the design of inorganic electrode ***,we review the cathode materials(Prussian blue and its analogues,layered oxides and poly anionic compounds)and the anode materials(antimony-based,selenium-based and bismuth-based compounds).On the basis of previous work,the structural design principles for improving the performance of electrode materials are reasonably *** the same time,the problems that need to be solved in the preparation of electrode materials and the direction of future research and improvement are pointed out.

关键词： Inorganic electrode materials Potassium-ion batteries Cathode materials Anode materials

Stability of the Phase Separation State for Compressible Navier-Stokes/Allen-Cahn System

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 45-74页

作者： ya-zhou chen Hakho Hong Xiao-ding Shi Department of Mathematics College of Mathematics and PhysicsBeijing University of Chemical TechnologyBeijing100029China Institute of Mathematics State Academy of SciencesPyongyangKorea

This paper is concerned with the large time behavior of the Cauchy problem for Navier-Stokes/AllenCahn system describing the interface motion of immiscible two-phase flow in 3-D. The existence and uniqueness of global solutions and the stability of the phase separation state are proved under the small initial perturbations. Moreover, the optimal time decay rates are obtained for higher-order spatial derivatives of density,velocity and phase. Our results imply that if the immiscible two-phase flow is initially located near the phase separation state, then under small perturbation conditions, the solution exists globally and decays algebraically to the complete separation state of the two-phase flow, that is, there will be no interface fracture, vacuum, shock wave, mass concentration at any time, and the interface thickness tends to zero as the time t → +∞.

关键词： Navier-Stokes/Allen-Cahn system existence uniqueness large time behavior decay rate