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Acta Metallurgica Sinica(English Letters) 2020年第8期33卷 1145-1150页

作者： Bang Dou Hui Zhang Jia-Hao Zhu Ben-qi Xu zi-Yi Zhou Ji-li Wu Key Laboratory of Green Fabrication and Surface Technology of Advanced Metal Materials(Ministry of Education) Anhui University of TechnologyMa'anshan 243002China School of Materials Science and Engineering Anhui University of TechnologyMa'anshan 243002China School of Materials Science and Engineering Jiangsu UniversityZhenjiang 212013China

A medium-entropy high-speed steel(ME-HSS)coating with the 76 at.%of Fe and multiple alloying elements was prepared by the wide-band laser *** with the commercial W6 Mo5 Cr4 V2(M2)HSS coating which contains a large number of network lamellar M2 C-type carbides along the grain boundaries,the presented ME-HSS coating has a high quantity of fi ner and more uniformly dispersed M C-type carbides;on the other hand,the coating has less retained austenite and much lower brittleness as well as similar secondary hardening eff ect and tempering hardness.

关键词： High-speed steel Medium-entropy alloy Phase selection Laser cladding

SYNTHESIS OF MAIN CHAIN liQUID CRYSTALliNE COPOLYESTERS WITH X-SHAPED TWO-DIMENSIONAL MESOGENIC UNIT AND CROWN ETHER CYCLE

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Chinese Journal of Polymer Science 2005年第5期23卷 549-556页

作者： Jing-wu Wang Shi-jun Zheng Xiao-hui Xu Xing-qi Zhu Shu-yuan Zhang Tie-sheng li zi-fa li qi-feng Zhou College of Materials and Engineering Zhengzhou UniversityZhengzhou 450052 China Department of Chemistry Zhengzhou UniversityZhengzhou 450052 China Department of Polymer Science and Engineering College of Chemistry and Molecular Engineering Peking University Beijing 100871China

A novel series of main chain liquid crystalline copolyesters with X-shaped two-dimensional mesogenic unit and crown ether cycle of cis-4,4＇-bis（4-hydroxyphenylazo） dibenzo-18-crown-6 was prepared via solution condensation polymerization from 4,4＇-（a;arhexanedioyloxy） dibenzoyl dichloride （MI）, 2,5-bis（p-octyloxybenzoyloxy） hydro-quinone （M2） and cis-4,4＇-bis（4-hydroxyphenylazo） dibenzo-18-crown-6 （M3）. Monomer MI was synthesized by esterification and substitution of adipoyl chloride with p-hydroxybenzoic acid, monomer M2 was synthesized by esterfication and reduction reaction of 2,5-dihydroxybenzoquinone and p-octanoxybenzoyl chloride and monomer M3 was synthesized by diazotization and coupling reaction of cis-diaminodibenzo-18-crown-6 with phenol. The molecular weights of copolyesters are not high, and the intrinsic viscosity [η] of copolyesters ranges from 0.25-0.35. The monomers＇ structures were identified by using elemental analysis, IR, UV, ^1H-NMR, MS, etc. All the copolyesters are yellowish powders and insoluble in THF and CHC13 at room temperature except cPg. The properties of copolyesters were investigated by using GPC, [η] , DSC, TG, WAXD and POM. It was found that all the copolyesters entered into liquid crystal phase when they were heated to above their melting temperature （Tin）. The typical smectic and nematic phase texture can be observed on POM. Their mesophase transition temperature and thermal stability change regularly with varying the content of cis-4,4＇-bis（4-hydroxyphenylazo） dibenzo-18-crown-6 unit in the copolyesters.

关键词： X-shaped two-dimensional mesogenic unit Crown ether liquid crystalline copolyesters Synthesis.

Neutral excitation and bulk gap of fractional quantum Hall liquids in disk geometry

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Chinese Physics B 2019年第6期28卷 20-26页

作者： Wu-qing Yang qi li lin-Peng Yang zi-Xiang Hu Department of Physics Chongqing UniversityChongqing 401331China Department of Physics South University of Science and Technology of ChinaShenzhen 518055China School of Physics and Technology Wuhan UniversityWuhan 430072China

For the numerical simulation of the fractional quantum Hall(FQH) effects on a finite disk, the rotational symmetry is the only symmetry that is used in diagonalizing the Hamiltonian. In this work, we propose a method of using the weak translational symmetry for the center of mass of the many-body system. With this approach, the bulk properties, such as the energy gap and the magneto-roton excitation are consistent with those in the closed manifolds like the sphere and torus. As an application, we consider the FQH phase and its phase transition in the fast rotated dipolar fermions. We thus demonstrate the disk geometry having versatility in analyzing the bulk properties beside the usual edge physics.

关键词： fractional quantum Hall bulk states edge states magneto-roton dipolar–dipolar interaction

Discovering genes responsible for silk synthesis in Bombyx moriby piggyBac-based random insertional mutagenesis

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Insect Science 2019年第5期26卷 821-830页

作者： Xing-Bao Feng zi-Wen Zheng Xian Zhang Jun Gu qi-li Feng li-Hua Huang Guangzhou Key Laboratory of Insect Development Regulation and Applied Research Institute of Insect Science and TechnologySchool of Life SciencesSouth China Normal UniversityGuangzhouChina

Silkworm mutants are valuable resources for both transgenic breeding and gene discovery. PiggyBac-based random insertional mutagenesis has been widely used in gene functional studies. In order to discover genes involved in silk synthesis, a piggyBac-based random insertional library was constructed using Bombyx mori, and the mutants with abnormal cocoon were particularly screened. By this means, a “thin cocoon” mutant was identified. This mutant revealed thinner cocoon shell and shorter posterior silk gland (PSG) compared with the wild type. The messenger RNA (mRNA) levels of all the three fibroin genes, including Fib-H, Fib-L and P25, were significantly down-regulated in the PSG of mutants. Four piggyBac insertion sites were identified in Aquaporin (AQP), Longitudinals lacking protein-like {Lola), Glutamyl aminopeptidase-like (GluAP) and Loc101744460. The mRNA levels of all the four genes were significantly altered in the silk gland of mutants. In particular, the mRNA amount of AQP, a gene responsible for the regulation of osmotic pressure, decreased dramatically immediately prior to the spinning stage in the anterior silk gland of mutants. The identification of the genes disrupted in the “thin cocoon” mutant in this study provided useful information for understanding silk production and transgenic breeding of silkworms in the future.

关键词： aquaporin Bombyx mori development mutant piggyBac silk gland

Effect of lanthanum on inclusions in non-oriented electrical steel slabs

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Journal of Iron and Steel Research International 2024年第7期31卷 1680-1691页

作者： qiang Ren Zhi-yuan Hu Yun-xia liu Wei-cheng Zhang zi-qi Gao li-feng Zhang School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004HebeiChina School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Research and Development Department Shougang Zhixin Qian'an Electromagnetic Material Co.Ltd.Qian'an 064400HebeiChina School of Mechanical and Materials Engineering North China University of TechnologyBeijing 100144China

The effect of lanthanum on the characteristics of inclusions in the slab of non-oriented electrical steels was investigated through industrial trials and thermodynamic *** number,size,and chemical composition of inclusions in the surface,one-quarter of thickness and the center of slabs with and without lanthanum addition were statistically analyzed using an automatic inclusion analysis *** the lanthanum-free slab,inclusions were predominately ***_(2)O_(3),MgO,and AlN as well as a small number of Al_(2)O_(3)-MgO-CaO and *** number densities of oxide inclusions and AlN decreased from the surface to the center of the slab,which was ascribed to the difference in cooling intensity during the continuous *** the steel with lanthanum addition,inclusions were modified into LaAlO_(3) and La_(2)O_(2)S and gradually transformed into dual-phase MgO-La_(2)S3 with an increasing distance from the slab surface due to the reaction between the lanthanum-containing inclusion and the steel *** uneven distribution of oxide inclusions along the thickness of the slab was eliminated in the lanthanum-bearing slab because the dissolved oxygen was remarkably decreased by ***-bearing inclusions were more likely to agglomerate AlN by inducing the heterogeneous nucleation of AlN on their surface,while small-size ***_(2)O_(3) inclusions hardly showed a coarsening effect on the size of AlN.

关键词： Lanthanum-Inclusion Non-oriented electrical steel Aluminum nitride Heterogenous nucleation

Formation and Developmental Characteristics of A- and B-Type Starch Granules in Wheat Endosperm

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Journal of Integrative Agriculture 2012年第1期11卷 73-81页

作者： YIN Yong-an qi Jun-cang li Wei-hua CAO lian-pu WANG zi-bu Key Oasis Eco-Agriculture Laboratory of Xinjiang Production and Construction Group/Agricultural Faculty Shihezi UniversityShihezi 832003P.R.China

Wheat grain natural transverse sections of 12 periods were observed and analyzed using scanning electron micrographs technology and Bio-Quant system IV image analyzer in order to detect the developing process of A- and B-type starch granules. In addition, the chemical composition and starch granule-bound proteins （SGPs） of A- and B-type starch granules were tested and analyzed. The results showed that A-type starch granules in wheat began from 3 d post anthesis （DPA） till grain maturing and B-type starch granules occured after 15 DPA till grain maturing. Approximately 98.5% of chemical compositions in both A- and B-type starch granules were amylose and amylopectin, and more than half of which were amylopectin. The amylopectin contents, average chain length, and chain length distribution （degree of polymerization〉 40） of amylopectin in A-type starch granules were significant higher than that of B-type starch granules. SGP-145, SGP-140, and SGP-26 kD were associated with A-type starch formation in wheat grain.

关键词： wheat (Triticum aestivum L.) A- and B-type starch granules formation and developmental characteristics

Study on the prediction and inverse prediction of detonation properties based on deep learning

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Defence Technology（防务技术） 2023年第6期24卷 18-30页

作者： zi-hang Yang Ji-li Rong zi-tong Zhao Department of Mechanics School of Aerospace EngineeringBeijing Institute of TechnologyBeijing100081China

The accurate and efficient prediction of explosive detonation properties has important engineering significance for weapon *** methods for predicting detonation performance include empirical formulas,equations of state,and quantum chemical calculation *** recent years,with the development of computer performance and deep learning methods,researchers have begun to apply deep learning methods to the prediction of explosive detonation *** deep learning method has the advantage of simple and rapid prediction of explosive detonation ***,some problems remain in the study of detonation properties based on deep *** example,there are few studies on the prediction of mixed explosives,on the prediction of the parameters of the equation of state of explosives,and on the application of explosive properties to predict the formulation of *** on an artificial neural network model and a one-dimensional convolutional neural network model,three improved deep learning models were established in this work with the aim of solving these *** training data for these models,called the detonation parameters prediction model,JWL equation of state(EOS)prediction model,and inverse prediction model,was obtained through the KHT thermochemical *** training,the model was tested for overfitting using the validation-set *** the model-accuracy test,the prediction accuracy of the model for real explosive formulations was tested by comparing the predicted value with the reference *** results show that the model errors were within 10%and 3%for the prediction of detonation pressure and detonation velocity,*** accuracy refers to the prediction of tested explosive formulations which consist of TNT,RDX and *** the prediction of the equation of state for explosives,the correlation coefficient between the prediction and the reference curves was above *** the prediction of the inverse predi

关键词： Deep learning Detonation properties KHT thermochemical Code JWL equation of states Artificial neural network One-dimensional convolutional neural network

Numerical simulation of climate response to ultraviolet irradiation forcing

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Advances in Climate Change Research 2019年第3期10卷 133-142页

作者： XIAO zi-Niu DONG Shi ZHONG qi State Key Laboratory o f Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute o f Atmospheric PhysicsChinese Academy of SciencesBeijing100029China China Meteorological Administration Training Centre China Meteorological AdministrationBeijing100081China

Using the Whole Atmosphere Community Climate Model, sensitivity experiments are performed to identify the climate response to ultra violet (UV) irradiation forcing. In the experiment, total solar irradiance (TSI) and solar spectral irradiation (SSI) are adopted as solar input from the dataset (1610 2009) reconstructed by Lean. Results show that UV variability has a strong impact on the middle atmosphere. Ozone (0 3) distribution in the atmosphere is sensitive to UV irradiation variability. When UV irradiation is enhanced, the 0 3 content increases at altitudes from 30 km to 60 km and decreases at altitudes from 15 km to 30 km. The atmospheric temperature appears positive anomaly below the mesosphere. Anomalous warmth develops above 35 km with maximum warming anomaly apparent at the stratopause, consistent with the at mospheric distribution of 0 3, which indicates that the ozone heating mechanism plays an important role in wanning. The 0 3 and temperature respond in an opposite manner when the UV irradiation is reduced. Furthermore, the stronger UV forcing leads to a change in the temperature distribution because of the 0 3 heating mechanism. This condition then modulates the zonal wind in the stratosphere and upper troposphere. Although the tropospheric response is weak on a global scale, a notable local response occurs over mid high latitudes in the Northern Hemisphere (NH) during winter. Along with the enhanced zonal wind in the lower stratosphere near the North Pole, the positive phase of the Arctic Oscillation pattern appears over the NH, which causes a temperature increase over mid-latitude Asia. Finally, the behavior evident in the reanalysis data is compared with the results of the numerical experiments. The similar structure of the response fields means the results of simulation experiment is credible to some extent.

关键词： Ultraviolet Ozone Climate variability Numerical simulation

Conclusions in Theory and Practice for Advancing the Applications of Cable-Driven Mechanisms

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Chinese Journal of Mechanical Engineering 2017年第4期30卷 763-765页

作者： Bin zi Yuan li School of Mechanical Engineering Hefei University ofTechnology Hefei 230009 China

The theoretical research of cable-driven mechanisms is developed with its broad applications. The first prototype of cable-driven mechanisms is RoboCrane, which was developed by the National Institute of Standards and Technology （NIST）. Then many excellent properties were developed and they have a variety of applications such as aerospace, aircraft and automobile industries [1]. Example application for RoboCrane in the field of aircraft mainte- nance is equipped with a quick-change mechanism to remove the robot arm remotely.

关键词： In more Conclusions in Theory and Practice for Advancing the Applications of Cable-Driven Mechanisms

Wear Behavior and Mechanism of Spheroidal Graphite Cast Iron

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Journal of Iron and Steel Research International 2013年第10期20卷 81-86页

作者： YANG zi-run li Dong-sheng WANG Lan WANG Shu-qi WEI Min-xian School of Materials Engineering Yancheng Institute of Technology School of Materials Science and Engineering Jiangsu University

Wear behavior and mechanism of spheroidal graphite cast iron were studied on a pin on-disk elevated tem- perature wear tester. The phase and morphology of worn surfaces were examined by X ray diffraction and scanning electron microscopy. Results show that with an increase of load, wear rate of spheroidal graphite cast iron gradually increases under low loads, rapidly increases or potentially increases under high loads; wear rate increases with in- creasing ambient temperature. At 25 200 ℃, adhesive wear prevails; oxidative wear and adhesive wear coexist at 400 ℃. As load surpasses 150 N at 400 ℃, extrusive wear appears. The elevated-temperature wear of spheroidal graphite cast iron is a physical and chemical process including the following reactions： xFe＋y/2O2-FexOy , 2C＋ O2- 2CO and Fex Oy ＋yCO-xFe＋yCO2. Hence, at 400 ℃, the amount of graphite and tribo oxides are substan- tially reduced because of reductive function of graphite. It can be suggested that wear reduced effect of graphite and tribo-oxides is impaired.

关键词： spheroidal graphite cast iron wear behavior wear mechanism tribo oxide microstructure