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BL03HB: a Laue microdiffraction beamline for both protein crystallography and materials science at SSRF

Nuclear Science and Techniques 2024年第7期35卷 68-78页

作者： zhi-Jun Wang Si-sheng Wang Zheng-Huang Su Li Yu Yu-Zhu Wang Bo Sun Wen Wen Xing-Yu gao Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai201210China University of Chinese Academy of Science Beijing100049China

A Laue microdiffraction beamline (BL03HB) was constructed at the Shanghai SynchrotronRadiation Facility (SSRF). This beamline featu res two consecutive focusing points in twodifferent sectors within its end station, the first dedicated to protein crystallography and theother tailored to materials science applications. Based on a superbend dipole magnet with amagnetic field of 2.29 T, a two-stage focusing design was implemented with two sets of Kirkpatrick- Baez mirrors to achieve a micro white beam as small as 4.2 um X4.3 pμm at the firstsector and 09 pum X 1.3 pum at the second sector in the standard beamline operation mode at *** X-ray microbeam in the two sectors can be easily switched between monochromatic andwhite beams by moving a four-bounce monochromator in or out of the light path, respectively. Inthe protein crystallography sector, white-beam Laue microdifraction was dermonstrated tosuccessully determine the structure of protein crystals from only a few images of diffraction data .collected by a Pilatus 2 M area detector. In the materials science sector, the white -beam Lauediffraction was collected in a reflection geometry using another Pilatus 2 M area detector, whichcould map the microstructural distribution on the sample surface by scanning the samples. Ingeneral, the BL03HB beamline promotes the application of Laue microdiffraction in both proteincrystallgraphy and materials science. This paper presents a comprehensive overview of theBL03HB beamline, end station, and the first commission results.

关键词： Crystallography White-beam Laue microdiffraction Beamline Synchrotron

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The effects of cool materials,façade orientation,and morphological parameters on energy consumption at the residential neighborhood scale

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Building Simulation 2024年第4期17卷 525-542页

作者： Fusuo Xu Dongdong Tian zhi gao Jianshun Jensen Zhang Department of Mechanical and Aerospace Engineering Syracuse UniversitySyracuseNY13210USA School of Architecture and Urban Planning Nanjing University22 Hankou RoadNanjingJiangsu Province210093China

Building surface cool materials are novel materials that can reduce urban heat island intensity and decrease building energy *** study investigated the impact of radiative properties of materials,façade orientation,and morphological parameters on energy consumption in six typical residential neighborhoods in Nanjing,*** neighborhood energy consumption of 16 application schemes considering the façade orientation factor is compared to determine the best energy-saving *** and annual energy-saving rates,savings in electricity costs,and the price ceiling for materials per unit area are *** results show that for low-rise buildings,using cool materials only on the roof can reduce the annual energy consumption by 1%.When cool or super cool materials are also used on the building façade,the annual energy saving rate can be up to 3.4%and 4.3%,*** cool materials on the south façade of buildings is not recommended due to significant heat loss in *** savings in electricity costs and the price ceiling for materials per unit area,the price of cool and super cool materials should be less than 3.0 and 3.7 RMB/m2,respectively,assuming a lifespan of eight years in Nanjing.

关键词： cool materials building energy saving neighborhood morphology façade orientation

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Spatial covariant gravity with two degrees of freedom in the presence of an auxiliary scalar field:Perturbation analysis

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Chinese Physics C 2024年第8期48卷 198-212页

作者： zhi-Chao Wang Xian gao School of Physics and Astronomy Sun Yat-sen UniversityZhuhai 519082China

We investigate a class of gravity theories respecting only spatial covariance,termed spatially covariant gravity,in the presence of an auxiliary scalar *** examine the conditions on the Lagrangian required to eliminate scalar degrees of freedom,allowing only two tensorial degrees of freedom to *** of strict constraint analysis,in this paper,we employ the perturbation method and focus on the necessary conditions to evade the scalar mode at the linear order in perturbations around a cosmological *** with a general action and solving the auxiliary perturbation variables in terms of a would-be dynamical scalar mode,we derive the condition to remove its kinetic term,thus ensuring that no scalar mode *** an application of the general condition,we study a polynomial-type Lagrangian as a concrete example,in which all monomials are spatially covariant scalars containing two *** find that the auxiliary scalar field is essential,and new terms in the Lagrangian are *** analysis provides insights into constructing gravity theories with two degrees of freedom in the extended framework of spatially covariant gravity.

关键词： modified gravity cosmological perturbation theory gravitational theory

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Precise Asymptotics in Limit Theorems for a Supercritical Branching Process with Immigration in a Random Environment

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Acta Mathematica Sinica,English Series 2024年第8期40卷 1850-1874页

作者： Chun Mao HUANG Rui ZHANG zhi Qiang gao Department of Mathematics Harbin Institute of Technology(Weihai)Weihai 264209P.R.China School of Mathematical Sciences Beijing Normal UniversityBeijing 100875P.R.China

Let(Zn)be a supercritical branching process with immigration in an independent and identically distributed random *** necessary moment conditions,we show the exact convergence rate in the central limit theorem on log Zn and establish the corresponding local limit theorem by using the moments of the natural submartingale and the convergence rates of its *** similar approach and with the help of a change of measure,we also present the so-called integrolocal theorem and integral large deviation theorem to characterize the precise asymptotics of the upper large deviations.

关键词： Branching process with immigration random environment central limit theorem large deviation

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In vivo imaging reveals a synchronized correlation among neurotransmitter dynamics during propofol and sevoflurane anesthesia

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Zoological Research 2024年第3期45卷 679-690页

作者： gao-Lin Qiu Li-Jun Peng Peng Wang zhi-Lai Yang Ji-Qian Zhang Hu Liu Xiao-Na Zhu Jin Rao Xue-sheng Liu Department of Anesthesiology First Affiliated Hospital of Anhui Medical UniversityHefeiAnhui 230022China School of Life Science and Technology ShanghaiTech UniversityShanghai 201210China

General anesthesia is widely applied in clinical ***,the precise mechanism of loss of consciousness induced by general anesthetics remains ***,we measured the dynamics of five neurotransmitters,includingγ-aminobutyric acid,glutamate,norepinephrine,acetylcholine,and dopamine,in the medial prefrontal cortex and primary visual cortex of C57BL/6 mice through in vivo fiber photometry and genetically encoded neurotransmitter sensors under anesthesia to reveal the mechanism of general anesthesia from a neurotransmitter *** revealed that the concentrations of γ-aminobutyric acid,glutamate,norepinephrine,and acetylcholine increased in the cortex during propofol-induced loss of *** levels did not change following the hypnotic dose of propofol but increased significantly following surgical doses of propofol ***,the concentrations of the five neurotransmitters generally decreased during sevoflurane-induced loss of ***,the neurotransmitter dynamic networks were not synchronized in the non-anesthesia groups but were highly synchronized in the anesthetic *** findings suggest that neurotransmitter dynamic network synchronization may cause anesthetic-induced loss of consciousness.

关键词： General anesthesia Loss of consciousness In vivo neurotransmitter imaging Medial prefrontal cortex Primary visual cortex

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Influence of friction-lubrication characteristics varying with rolling speed on instability of chatter and slip in cold tandem rolling process

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Journal of Iron and Steel Research(International) 2024年第4期31卷 894-908页

作者： Yan-li Xin zhi-ying gao Bo Tian Qing-dong Zhang School of Mechanical Engineering University of Science and Technology BeijingBeijing 100083China

In the high-speed cold tandem rolling process of thin plate,chatter or slip instability gives rise to the deterioration of equipment and product *** instability behavior is closely related to interfacial friction-lubrication con-dition which is generally characterized by the friction ***,with higher and higher speed requirements,the commonly used model of friction coefficient is no longer applicable and accurate.A novel approach is suggested to calculate the speed-dependent friction coefficient,in which the viscosity-pressure-temperature effects of the lubricant,surface roughness states of work rolls and rolled piece are comprehensively involved and the mixed flm lubrication theory is ***,the influences of friction coefficient on the instability of slip and chatter are investigated for a five-stand cold tandem rolling *** one side,the critical friction coefficient for each stand is determined by calculating the corresponding slip factor;on the other hand,the friction coefficient varying with rolling speed is combined with the model of theoretical critical rolling speed presented under constant friction coefficient,so that the speed threshold is ***,the stable and unstable regions corresponding to the rear three stands are individually discussed,and the technical strategies are proposed to suppress both slip and chatter frequently occurring in the actual rolling process.

关键词： Cold tandem rolling:Oil film thickness Speed-dependent friction coefficient-Slip:Chatter

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Asymptotic normality of error density estimator in stationary and explosive autoregressive models

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 140-158页

作者： WU Shi-peng YANG Wen-zhi gao Min HU Shu-he School of Mathematical Sciences&School of Big Data and Statistics Anhui UniversityHefei 230601China School of Statistics Shanxi University of Finance and EconomicsTaiyuan030006China

In this paper,we consider the limit distribution of the error density function estima-tor in the rst-order autoregressive models with negatively associated and positively associated random *** mild regularity assumptions,some asymptotic normality results of the residual density estimator are obtained when the autoregressive models are stationary process and explosive *** order to illustrate these results,some simulations such as con dence intervals and mean integrated square errors are provided in this *** shows that the residual density estimator can replace the density\estimator"which contains errors.

关键词： explosive autoregressive models residual density estimator asymptotic distribution association sequence

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Synergistic effect of Zr and Mo on precipitation and high-temperature properties of Al-Si-Cu-Mg alloys

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China Foundry 2024年第1期21卷 71-81页

作者： Chao gao Bing-rong Zhang Yin-ming Li zhi-ming Wang Xiang-bin Meng Faculty of Mechanical Engineering Qilu University of Technology(Shandong Academy of Sciences)Jinan 250353China Hebei Ounai Machinery Mould Co.Ltd. Xingtai 054500HebeiChina

This study focuses on finding a solution to the sharp decline in mechanical properties of Al-Si-Cu-Mg alloys due to rapid coarsening of traditional intermediate phases at high temperature.A new type of modified al oy,to be used in automobile engines at high temperatures,was prepared by adding Zr and Mo into Al-Si-Cu-Mg *** synergistic effects of Zr and Mo on the microstructure evolution and high-temperature mechanical properties were *** show that the addition of Zr and Mo generates a series of intermetallic phases dispersed in the *** can improve the strength of the alloy by hindering dislocation movement and crack *** addition,some nano-strengthened phases show coherent interfaces with the matrix and improve grain *** addition of Mo greatly improves the heat resistance of the *** extremely low diffusivity of Mo enables it to improve the thermal stability of the intermetallic phases,inhibit precipitation during aging,reduce the size of the precipitates,and improve the heat resistance of the alloy.

关键词： Al-Si-Cu-Mg alloy high-temperature properties Zr-Mo-rich intermetallics nano-strengthening phases

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Strip flatness prediction of cold rolling based on ensemble methods

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Journal of Iron and Steel Research(International) 2024年第1期31卷 237-251页

作者： Wu-quan Yang zhi-ting Zhao Liang-yu Zhu Xun-yang gao Li Wang School of Mechanical and Power Engineering Shenyang University of Chemical TechnologyShenyang110142LiaoningChina

Aiming at the problem of insufficient prediction accuracy of strip flatness at the outlet of cold tandem rolling,the prediction performance of strip flatness based on different ensemble methods was studied and a high-precision prediction ensemble model of strip flatness at the outlet was ***,based on linear regression(LR),K nearest neighbors(KNN),support vector regression,regression trees(RT),and backpropagation neural network(BPN),bagging,boosting,and stacking ensemble methods were used for ensemble ***,three existing ensemble models,i.e.,random forest,extreme random tree(ET)and extreme gradient boosting,were used to conduct experiments and compare the *** research shows that bagging,boosting,and stacking three ensemble methods have the most significant improvement in the prediction accuracy of the regression trees model,which is increased by 5.28%,6.51%,and 5.32%,*** the same time,the stacking ensemble method improves both the simple model and the complex model,and the improvement effect on the simple base model is the greatest,which is 4.69%higher than that of the base model *** all of the ensemble models,the stacking ensemble model of level-1(ET,AdaBoost-RT,LR,BPN)paired with level-2(LR)was discovered to be the best model(EALB-LR)and can be further studied for industrial applications.

关键词： Tandem cold rolling Flatness prediction Machine learning Ensemble method

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Convenient room-temperature synthesis of sulfur and nitrogen co-doped NiCo-LDH coupled with CNTs on NiCo foam as battery-type electrode for high performance hybrid supercapacitor

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Rare Metals 2024年第9期43卷 4286-4301页

作者： Li Song Xiao-Hong Zhong Fang-Lin Wang zhi-Hui Huang Zhe Hong Yun-Fang gao Hai-Dong Wang Jian-Wei Ren sheng-Jie Peng Lei Li College of Biological Chemical Sciences and EngineeringJiaxing University College of Chemical Engineering Zhejiang University of Technology College of Materials Science and Technology Nanjing University of Aeronautics and Astronautics Research and Development Department Jiangxi Ganfeng Li Energy Technology Co.Ltd. Department of Mechanical Engineering Science University of Johannesburg

The convenient synthesis of the composite electrode with high supercapacitance performance plays an important role in practical application but is ***, the carbon nanotubes（CNTs） coupled with lowcrystalline sulfur and nitrogen co-doped Ni Co-LDH（denoted as SN-Ni Co-LDH） nanosheets array are grown on Ni Co foam（NCF） substrate by two convenient steps of metal induced self-assembly and corrosion engineering,which present the advantages of operating at roomtemperature and low preparation costs. Benefiting from the S–N co-doping and low-crystallinity of Ni Co-LDH, the prepared SN-Ni Co-LDH@CNTs@NCF electrode presents a topping charge capacity of 2470 C·g-1(4.94 C·cm-2) at 5 m A·cm-2. Furthermore, the fabricated asymmetry supercapacitor（ASC） achieves an extraordinary energy density of 77 Wh·kg-1(0.617 m Wh·cm-2) at a power density of 438 W·kg-1(3.5 m W·cm-2) and outstanding stability(91% capacity retention after 5000 cycles at20 m A·cm-2). Impressively, the structure evolution of Ni Co-LDH during the charge/discharge processes has been thoroughly elucidated by in-situ Raman spectra. Therefore,this work verifies a powerful strategy and practical value for preparing composite electrodes with high supercapacitance performance, and also provides guidance for the rational design of the smart electrodes.

关键词： Carbon nanotubes Convenient synthesis NiCo-LDH Sulfur and nitrogen co-doped Supercapacitor

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