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Effects of Welding Speed and Post-weld Hot Rolling on Microstructure and Mechanical Properties of Friction Stir-Welded AZ31 Magnesium Alloy

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Acta Metallurgica Sinica(English Letters) 2018年第8期31卷 853-864页

作者： Gang Liu Li-Na Ma Zhen-Duo Ma Xue-Song Fu Guo-Bing Wei Yan Yang tian-cai Xu Wei-Dong Xie Xiao-Dong Peng College of Materials Science and Engineering Chongqing UniversityChongqing 400044China National Engineering Research Center for Magnesium Alloys Chongqing 400044China

The as-rolled AZ31 Mg alloy sheets are welded by friction stir welding（FSW） in this study, followed by annealing and hot rolling with different reductions. The effects of welding speed and the rolling reduction on the microstructure, tensile properties, microhardness and fracture surfaces of the specimens are investigated. The results show that the microstructures of the FSW joint in different regions become more and more consistent as the hot rolling reduction increases. The mechanical properties of the FSW joints and the joint coefficient are improved with increasing rolling reduction; however,the hardness value in the stirred zone decreases firstly and then increases. When the rolling reduction is 50%, the tensile strength of FSW joint is close to that of base metal. The sample L_3 achieves the best comprehensive properties, with the yield strength, ultimate tensile strength and elongation of 162, 287.9 MPa, and 17.9%, respectively.

关键词： Magnesium alloy FSW Post-weld hot rolling Microstructure Mechanical properties

Tunable Optical Bandpass Filter via a Microtip-Touched Tapered Optical Fiber

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Chinese Physics Letters 2020年第10期37卷 26-32页

作者： Peng-Fei Zhang Li-Jun Song Chang-Ling Zou Xin Wang Chen-Xi Wang Gang Li tian-cai Zhang State Key Laboratory of Quantum Optics and Quantum Optics Devices Institute of Opto-ElectronicsShanxi UniversityTaiyuan 030006China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China CAS Key Laboratory of Quantum Information University of Science and Technology of ChinaHefei 230026China

We demonstrate a tunable bandpass optical filter based on a tapered optical fiber(TOF)touched by a hemispherical microfiber tip(MFT).Other than the interference and selective material absorption effects,the filter relies on the controllable and wavelength-dependent mode–mode interactions in ***,a large range of tunability is realized by controlling the position of the MFT in contact with the TOF for various TOF radii,and two distinct bandpass filter mechanisms are *** center wavelength of the bandpass filter can be tuned from 890 nm to 1000 nm,while the FWHM bandwidth can be tuned from 110 nm to 240 nm when the MFT touches the TOF in the radius range from 160 nm to 390 *** distinction ratio can reach 28±3 dB *** combined TOF-MFT is an in-line tunable bandpass optical filter that has great application potential in optical networks and spectroscopy,and the principle could also be generalized to other integrated photonic devices.

关键词： tunable fiber Touch

Cavity enhanced measurement of trap frequency in an optical dipole trap

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Chinese Physics B 2019年第4期28卷 165-169页

作者： Peng-Fei Yang Hai He Zhi-Hui Wang Xing Han Gang Li Peng-Fei Zhang tian-cai Zhang State Key Laboratory of Quantum Optics and Quantum Optics Devices Institute of Opto-ElectronicsShanxi University Collaborative Innovation Center of Extreme Optics Shanxi University

We demonstrate a direct, fluorescence-free measurement of the oscillation frequency of cold atoms in an optical dipole trap based on a high-finesse optical cavity strongly coupled to atoms. The parametric heating spectra of the trapped atoms are obtained by recording the transmitted photons from the cavity with the trap depth is modulated by different ***, in our method the oscillation can be observed directly in the time scale. Being compared to the conventional fluorescence-dependent method, our approach avoids uncertainties associated with the illuminating light and auxiliary imaging optics. This method has the potential application of determining the motion of atoms with stored quantum bits or degenerate gases without destroying them.

关键词： cavity QED oscillation frequency

Grain yield and water use of winter wheat as affected by water and sulfur supply in the North China Plain

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Journal of Integrative Agriculture 2017年第3期16卷 614-625页

作者： XIE Ying-xin ZHANG Hui ZHU Yun-ji ZHAO Li YANG Jia-heng CHA Fei-na LIU Cao WANG Chen-yang GUO tian-cai State Key Laboratory of Wheat and Maize Crop Science Henan Agricultural University Zhengzhou 450002 P.R.China College of Resources and Environment Henan Agricultural University Zhengzhou 450002 P.R. China Zhoukou Academy of Agricultural Sciences Zhoukou 466001 P.R. China Zhengzhou Meteorological Bureau Zhengzhou 450000 P.R. China

Water shortage has threatened sustainable development of agriculture globally as well as in the North China Plain（NCP）.Irrigation,as the most effective way to increase food production in dry land,may not be readily available in the situation of *** of the alternatives is to supply plants with enough nutrients so that they can be more sustainable to the water *** objective of this study was to explore effects of irrigation and sulphur（S）application on water consumption,dry matter accumulation（DMA）,and grain yield of winter wheat in *** irrigation regimes including no irrigation（rainfed,I0）during the whole growth period,once irrigation only at jointing stage（90 mm,I1）,and twice respective irrigation at jointing and anthesis stages（90 mm plus 90 mm,I2）,and two levels of S application including 0S0and 60 kg ha^–1（S60）were designed in the field experiment in *** showed that increasing irrigation times significantly increased mean grain yield of wheat by 12.5–23.7%and nitrogen partial factor productivity（NPFP）by 21.2–45.0%in two wheat seasons,but markedly decreased crop water use efficiency（YWUE）.Furthermore,S supply 60 kg ha^–1 significantly increased mean grain yield,YWUE,IWUE and NPFP by 5.6,6.1,23.2,and 5.6%（across two wheat seasons）,***,we also found that role of soil moisture prior to S application was one of important greater factors on improving the absorption and utilization of storage water and nutrients of ***,water supply is still the most important factor to restrict the growth of wheat in the present case of NCP,supplying 60 kg ha^–1 S with once irrigation 90 mm at the jointing stage is a relatively appropriate recommended combination to improve grain yield and WUE of wheat when saving water resources is be considered in irrigated wheat farmlands of NCP.

关键词： sulphur irrigation winter wheat grain yield water use efficiency 1

Microbial community composition and environmental response characteristics of typical brackish groundwater in the North China Plain

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China Geology 2023年第3期6卷 383-394页

作者： Huai-sheng Zhang Wu-tian cai Feng Guo Chao Bian Fu-dong Liu Lei Zhang Jin-wei Liu Miao Zhao Center for Hydrogeology and Environmental Geology Survey CGSBaoding 071051China National Research Center for Geoanalysis Key Laboratory of Eco-GeochemistryMinistry of Natural ResourcesBeijing 10037China Third Hydrological Engineering Geological Brigade Hebei Bureau of Geology and Mineral ResourcesHengshui 053000China

To reveal the microbial community composition of regional shallow porous brackish groundwater and its response characteristics to groundwater environment,the first and second aquifers in Taocheng District,Hengshui City were selected,and 10 groundwater source samples were collected for hydrochemical analysis and microbial 16S RNA gene V4-V5 regional *** results showed that the shallow brackish groundwater in the study area is weakly alkaline and has high ion *** hydrochemical types are SO_(4)·Cl-Na·Mg type and HCO3·Cl-Na·Mg type as a *** spatial zonation of the abundance and diversity of groundwater microorganisms is *** number of endemic bacteria in groundwater from upstream,midstream to downstream is 11,135 and 22 respectively,with a total of 22 *** is the most dominant in groundwater level(38.82%-86.88%),and there are obvious differences in different *** the genus level,the main dominant species in each group and sample are Pseudomonas and *** terms of composition difference,Pseudohongiella,Pseudorhodobacter and Limnohabitans are the representatives of UR,MR and *** the whole,the composition of flora in groundwater in the study area is sensitive and closely related to hydrochemical *** abundance is affected by alkaline and high salinity environmental indicators,while species diversity is related to depth and dissolved oxygen in weak reduction environment.

关键词： Groundwater microorganism Microbial Endemic bacteria Biochemistry Pseudomonas Hydrogenophage Brackish groundwater Environmental response Hydrogeological survey engineering Environmental geological survey engineering

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铁电体的光伏效应

物理学报 2018年第15期67卷 228-240页

作者：蔡田怡雎胜苏州大学物理科学与技术学院苏州215006

介绍了铁电光伏效应的发展历史和现状,通过与传统半导体p-n结光伏器件比较,旨在阐述铁电光伏器件非比寻常的优点和重要的应用前景.铁电光伏效应分为体光伏效应和反常光伏效应,多种物理机制已被发现,无疑为铁电光伏效应的提高指明了方向... 详细信息

介绍了铁电光伏效应的发展历史和现状,通过与传统半导体p-n结光伏器件比较,旨在阐述铁电光伏器件非比寻常的优点和重要的应用前景.铁电光伏效应分为体光伏效应和反常光伏效应,多种物理机制已被发现,无疑为铁电光伏效应的提高指明了方向.还对钙钛矿氧化物、卤化物和双钙钛矿结构氧化物等铁电体中的光伏效应进行了阐述,讨论了通过引入新的自由度实现多功能性光伏器件的可能性.

关键词：铁电体光伏效应多铁性材料太阳能电池

Influence of Geometric Structure of Immobilized Aluminium Chloride Catalyst on Catalytic Property in Isobutene Polymerization

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Chinese Chemical Letters 2001年第7期12卷 647-650页

作者： tian Xi cai, Min HE, Xian Zhe SHI, Xin Ping WANG State Key Laboratory for Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, Dalian 116012 Dalian Univ Technol Sch Chem Engn State Key Lab Fine Chem Dalian 116012 Peoples R China

The catalytic property of AICl(3) catalyst immobilized on gamma -Al2O3 for isobutene polymerization has been studied. It was found that the activity, selectivity and stability of the catalyst are dependent greatly on geometric characteristic pf the pore structure and size of catalyst. Although the activity and selectivity of the catalysts with micro- and meso-pore structure are all high in initial stage, but their stability is low, while those with bimodal meso- and macro-pore structure are excellent. Increasing granularity of the catalyst(particle become fine) brings about an increase in isobutene conversion, but a decrease in selectivity, resulting in lower average molecular weight and iis broader distribution.

关键词： AlCl3 immobilization gamma-Al2O3 bimodal meso- and macro-pore structure isobutene polymerization stability

Leech Poecilobdella manillensis protein extract ameliorated hyperuricemia by restoring gut microbiota dysregulation and affecting serum metabolites

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World Journal of Gastroenterology 2024年第29期30卷 3488-3510页

作者： Xia Liu Xing-Qiu Liang tian-cai Lu Zhe Feng Min Zhang Nan-Qing Liao Feng-Lian Zhang Bo Wang Li-Sheng Wang Medical College Guangxi UniversityNanning 530004Guangxi Zhuang Autonomous RegionChina Department of Traditional Chinese Medicine HIV/AIDS Clinical Treatment Center of Guangxi(Nanning)The Fourth People’s Hospital of NanningNanning 530023Guangxi Zhuang Autonomous RegionChina Department of Science and Technology Ruikang Hospital Affiliated to Guangxi University of Chinese MedicineNanning 530011Guangxi Zhuang Autonomous RegionChina General Manager’s Office Guangxi Fuxinyi Biological Technology Co.Ltd.Pingnan 537300Guangxi Zhuang Autonomous RegionChina Department of Joint and Sports Medicine Ruikang Hospital Affiliated to Guangxi University of Chinese MedicineNanning 530011Guangxi Zhuang Autonomous RegionChina Department of Gerontology Nanning Social Welfare HospitalNanning 530004Guangxi Zhuang Autonomous RegionChina

BACKGROUND Hyperuricemia(HUA)is a public health concern that needs to be solved *** lyophilized powder of Poecilobdella manillensis has been shown to significantly alleviate HUA;however,its underlying metabolic regulation remains *** To explore the underlying mechanisms of Poecilobdella manillensis in HUA based on modulation of the gut microbiota and host *** A mouse model of rapid HUA was established using a high-purine diet and potassium oxonate *** mice received oral drugs or ***,16S rRNA sequencing and ultra-high performance liquid chromatography with quadrupole time-of-flight mass spectrometry-based untargeted metabolomics were performed to identify changes in the microbiome and host metabolome,*** levels of uric acid transporters and epithelial tight junction proteins in the renal and intestinal tissues were analyzed using an enzyme-linked immunosorbent *** The protein extract of Poecilobdella manillensis lyophilized powder(49 mg/kg)showed an enhanced anti-trioxypurine ability than that of allopurinol(5 mg/kg)(P<0.05).A total of nine bacterial genera were identified to be closely related to the anti-trioxypurine activity of Poecilobdella manillensis powder,which included the genera of Prevotella,Delftia,Dialister,Akkermansia,Lactococcus,Escherichia_Shigella,Enterococcus,and ***,22 metabolites in the serum were found to be closely related to the anti-trioxypurine activity of Poecilobdella manillensis powder,which correlated to the Kyoto Encyclopedia of Genes and Genomes pathways of cysteine and methionine metabolism,sphingolipid metabolism,galactose metabolism,and phenylalanine,tyrosine,and tryptophan *** analysis found that changes in the gut microbiota were significantly related to these *** The proteins in Poecilobdella manillensis powder were effective for ***,they are associated with improvements in g

关键词： Gut microbiota Metabolism Multi-omics Poecilobdella manillensis Sphingolipid metabolism pathway Galactose metabolism pathway Hyperuricemia

Helicobacter pylori plays a key role in gastric adenocarcinoma induced by spasmolytic polypeptide-expressing metaplasia

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World Journal of Clinical Cases 2023年第16期11卷 3714-3724页

作者： Mian-Li Li Xin-Xin Hong Wei-Jian Zhang Yi-Zhong Liang tian-tian cai Yi-Fei Xu Hua-Feng Pan Jian-Yuan Kang Shao-Ju Guo Hai-Wen Li Department of Gastroenterology Shenzhen Hospital of IntegratedTraditional Chinese and Western MedicineShenzhen 518033Guangdong ProvinceChina Department of Gastroenterology Shenzhen Traditional Chinese Medicine HospitalShenzhen 518033Guangdong ProvinceChina Science and Technology Innovation Center Guangzhou University of Traditional Chinese MedicineGuangzhou 510405Guangdong ProvinceChina

Heliobacter pylori(H. pylori), a group 1 human gastric carcinogen, is significantly associated with chronic gastritis, gastric mucosal atrophy, and gastric *** 20% of patients infected with H. pylori develop precancerous lesions, among which metaplasia is the most critical. Except for intestinal metaplasia(IM), which is characterized by goblet cells appearing in the stomach glands, one type of mucous cell metaplasia, spasmolytic polypeptide-expressing metaplasia(SPEM), has attracted much attention. Epidemiological and clinicopathological studies suggest that SPEM may be more strongly linked to gastric adenocarcinoma than IM. SPEM, characterized by abnormal expression of trefoil factor 2, mucin 6, and Griffonia simplicifolia lectin II in the deep glands of the stomach, is caused by acute injury or inflammation. Although it is generally believed that the loss of parietal cells alone is a sufficient and direct cause of SPEM, further in-depth studies have revealed the critical role of *** is controversy regarding whether SPEM cells originate from the transdifferentiation of mature chief cells or professional progenitors. SPEM plays a functional role in the repair of gastric epithelial injury. However, chronic inflammation and immune responses caused by H. pylori infection can induce further progression of SPEM to IM, dysplasia, and adenocarcinoma. SPEM cells upregulate the expression of whey acidic protein 4-disulfide core domain protein 2 and CD44 variant 9, which recruit M2 macrophages to the wound. Studies have revealed that interleukin-33, the most significantly upregulated cytokine in macrophages, promotes SPEM toward more advanced metaplasia. Overall, more effort is needed to reveal the specific mechanism of SPEM malignant progression driven by *** infection.

关键词： Gastric cancers Helicobacter pylori Intestinal metaplasia Macrophages Spasmolytic polypeptide-expressing metaplasia