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1Hermetia illucens larvae as a potential dietary protein source altered the microbiota and modulated mucosal immune status in the colon of finishing pigs显示文摘Background: Insects, such as Hermetia illucens larvae, are rich in chitin and proteins, and represent a suitable feed ingredient replacement for animals. However, little is known about the effect of administering H. illucens larvae on intestinal microbiota, bacterial metabolite profiles, and mucosal immune status in animals. This study aimed to investigate the effects of administering H. illucens larvae on colonic microbiota and bacterial metabolites production in finishing pigs. Seventy-two crossbred(Duroc × Landrace × Large White) female pigs(initial body weight, 76.0 ± 0.52 kg) were randomly allocated to three different dietary treatments: a control diet(Control group) and two diets corresponding to 4%(H1 group) and 8%(H2 group) H. illucens larvae inclusion levels, respectively. Each treatment consisted of eight pens(replicates), with three pigs per pen. After 46 days of feeding, eight pigs per treatment(n =8) were slaughtered, and the colonic digesta and mucosa were collected for microbial composition and microbial fermentation products, and genes expression analyses.Results: The results showed that the H1 diet significantly increased the abundance of Lactobacillus,Pseudobutyrivibrio, Roseburia, and Faecalibacterium compared with those in the control group(P < 0.05), with a decrease in the abundance of Streptococcus. The numbers of Lactobacillus, Roseburia, and Clostridium cluster XIVa were significantly greater in the H1 group than in the control group(P < 0.05). Meanwhile, H2 diet increased the number of Clostridium cluster XIVa compared with the control group(P < 0.05). For colonic metabolites, total short chain fatty acids, butyrate, and isobutyrate concentrations were significantly higher in the H1 group than those in the control group(P < 0.05);the H1 treatment caused a striking decrease in protein fermentation compared with the control group, as the concentrations of total amines, cadaverine, tryptamine, phenol, p-cresol, and skatole were significantly lower(P < 0.05). Additionally, H2 diet also increased butyrate concentration compared with control group(P < 0.05), while decreased the concentrations of phenol, p-cresol, and skatole(P < 0.05). Pigs in the H1 group down-regulated the expression of TLR-4 and pro-inflammatory cytokines(IFN-γ) compared with pigs in the control group(P < 0.05), and up-regulated anti-inflammatory cytokine(IL-10) and intestinal barrier genes(ZO-1, occludin, and mucin-1). H2 diet up-regulated the expression of ZO-1 compared with control group(P < 0.05). Furthermore, the changes in the colonic mucosal gene expression were associated with changes in the bacterial composition and their metabolites.Conclusions: Collectively, dietary inclusion of Hermetia illucens larvae may enhance mucosal immune homeostasis of pigs via altering bacterial composition and their metabolites. These findings provide a new perspective on insect meal as a sustainable protein source rich in nutrient ingredients for swine.Miao Yu Zhenming Li Weidong Chen Ting Rong Gang Wang Xianyong Ma 2019Journal of Animal Science and Biotechnology2019,10,4:21
2Discharge Characteristics of Long SF6 Gas Gap with and Without Insulator in GIS Under VFTO and LI显示文摘Gas insulator switchgears(GISs),widely used in electric power systems for decades,have many advantages due to their compactness,minimal environmental impact,and long maintenance cycles.However,very fast transient overvoltage(VFTO)increases caused by a rise in voltage levels can lead to GIS insulation failures.In this paper,a generating system of VFTO and standard lightning impulse(LI)is established.The insulation characteristics of SF6 gas with and without insulators under VFTO and standard LI are investigated.Experimental results show that the 50%breakdown voltages of the inhomogeneous electric field rod-plane gap under positive VFTO and standard LI are higher than that under negative VFTO and standard LI.The research shows that the 50%breakdown voltage under VFTO could be lower than that under standard LI at 0.5 MPa for the negative polarity.Moreover,the polarity effect of the insulator without defect is different from that with defect.Similarly,the breakdown voltage of the defective insulator under VFTO could be lower than that under standard LI by 8%.The flashover channel under VFTO is seen as more than that under standard LI.Based on the analysis of discharge images and experimental results,it is concluded that the polarity effect is related to the distortion effect of ion clusters formed by SF6 on the electric field.Additionally,the steepness and front time of impulse plays an important role in the initiation and further development of discharge on insulator surface.Finally,the research shows that different discharge characteristics between VFTO and standard LI may be caused by different wave fronts and oscillation on the tails of the impulses.Tao Wen Qiaogen Zhang Jingtan Ma Can Guo Haoyang You Yifan Qin Yu Yin Weidong Shi Weijiang Chen 2015CSEE Journal of Power and Energy Systems2015,1,3:17
3High-precision timing of the Quaternary standard samples with thermal ionization mass spectrometry (TIMS) U-series method显示文摘Two national stalagmite standard (GBW04412, GBW04413) and one international coral standard (RKM4) have been determined by using thermal ionization mass spectrometry (TIMS) method. The values of ( 234 U/ 238 U) act , ( 230 Th/ 234 U) act and age are all consistent in error range with the standard values obtained by using α spectrometry.Peng Zicheng Wang Zhaorong Sun Weidong Ma Zhibang Xia Ming Zhang Chenhui Chen Wenji Zhang Zhonglu An Zhisheng 1998Chinese Science Bulletin1998,43,4:14
4Different dietary starch sources alter the carcass traits, meat quality, and the profile of muscle amino acid and fatty acid in finishing pigs显示文摘Background: With increasing health awareness among consumers, the demand for healthier, tastier, higher quality and nutritional value pork is increasing. It has been shown that different dietary starch sources can alter the carcass traits and meat quality. However, research on the effects of different starch sources with clear different amylose/amylopectin ratio on the amino acid and fatty acid composition in Longissimus thoracis(L. thoracis) muscle of pigs is limited. This study aimed to investigate the effects of different dietary starch sources on carcass traits, meat quality, muscle amino acid and fatty acid composition, and the mRNA expression levels of genes involved in lipid metabolism and muscle fiber characteristics in finishing pigs. A total of 72 Duroc × Landrace × Large White barrows were randomly allocated to 3 different dietary treatment groups with 8 replicate pens/group and 3 pigs per pen.Tapioca starch(TS), corn starch(CS), and pea starch(PS), with amylose/amylopectin ratio of 0.11, 0.25, and 0.44,respectively, were used as their dietary starch sources for 40 days.Results: Results showed that the PS diet significantly increased(P < 0.05) the final body weight, average daily gain,loin-eye area, and fat-free lean index compared with the TS diet, but significantly decreased(P < 0.05) the feed to gain ratio and backfat thickness. Compared with the TS diet, PS diet also increased(P < 0.05) the pH45 min, marbling scores, the content of intramuscular fat and inosine monophosphate in the L. thoracis, and decreased(P < 0.05) the drip loss and shear force. In addition, compared with the TS diet, PS diet increased(P < 0.05) the proportions of flavor amino acids, DHA, EPA, and n-3 polyunsaturated fatty acid(PUFA) in the L. thoracis compared with TS diet,but decreased(P < 0.05) the ratio of n-6/n-3 PUFA. Furthermore, compared with the TS diet, PS diet also upregulated(P < 0.05) the lipogenic genes(FAS, LPL, SCD, ACCα) and myosin heavy-chain(MyHC)-IIa mRNA expression levels compared with the TS diet, but downregulated(P < 0.05) the CPT1 B and MyHC-IIb mRNA levels.Conclusions: In conclusion, these results provided compelling evidence that the different dietary starch source altered the carcass traits, meat flavor and quality in finishing pigs, and consumption of a diet with higher amylose/amylopectin ratio results in the production of a healthy, higher quality, and nutritional value pork.Miao Yu Zhenming Li Ting Rong Gang Wang Zhichang Liu Weidong Chen Jiazhou Li Jianhao Li Xianyong Ma 2021Journal of Animal Science and Biotechnology2021,12,1:13
5A review on China's constructed wetlands in recent three decades:Application and practice显示文摘Constructed wetlands(CWs)have been introduced to and developed in China for environmental engineering over the most prosperous three decades(1990–2020).To study the origin,development process,and future trend of CWs,this review summarized a wide range of literatures between 1990 and 2020 by Chinese authors.Firstly,the publication number over years,research highlights,and the author contributions with the most published papers in this field were conducted through bibliometric analysis.Secondly,the most principal components of CWs,substrates and macrophytes were summarized and analyzed.Thirdly,the typical application cases from traditional CWs,pond systems to combined pond-wetland systems were presented.In China,CWs were predominately distributed in the east of the so-called'Hu Huanyong Line'.Therefore CWs were limited by the socio-economic level and climatic conditions.It is unquestionable that the overall level of China's CWs has improved significantly,and one of the most prominent features has started towards the plural pattern development.There has been a trend of large-scale or low-cost CW application in the recent years.However,lifecycle research and management are required for better strategies in the future.Hong Zhang Wenzhong Tang Weidong Wang Wei Yin Honglei Liu Xiaomin Ma Yiqi Zhou Pei Lei Dongyang Wei Litian Zhang Cao Liu Jinmiao Zha 2021Journal of Environmental Sciences2021,33,6:13
6Ethylene oligomerization by novel iron(Ⅱ) diimine complexes/MAO显示文摘Two novel Fe(Ⅱ) diimine complexes have been synthesized. In combination with MAO, they generate active catalytic systems that oligomerize ethylene with both high catalytic activity and high selectivity for a-olefins. The effects of substituents on the aryl ring, reaction temperatures and molar ratios of Al/Fe on catalytic activity and product distribution are studied.WANG Hang, YAN Weidong, JIANG Tao, LIU Binbin, XU Wenqing, MA Jianjiang & HU YouliangState Key Laboratory of Engineering Plastics, Center for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China Graduate Student of 2002Chinese Science Bulletin2002,47,19:8
7sLe^(x) expression in invasive micropapillary breast carcinoma is associated with poor prognosis and can be combined with MUC1/EMA as a supplementary diagnostic indicator显示文摘Objective: Mucin 1(MUC1/EMA) and sialyl Lewis X(sLe^(x)) indicate polarity reversal in invasive micropapillary carcinoma(IMPC). The purpose of this study was to evaluate the expression of MUC1/EMA and sLe^(x) and to assess their diagnostic and prognostic value in patients with IMPC.Methods: The expression of sLe^(x) and MUC1/EMA in 100 patients with IMPC and a control group of 89 patients with invasive ductal carcinoma not otherwise specified(IDC-NOS) were analyzed with IHC. Fresh tumor tissues were collected from patients with IMPC or IDC-NOS for primary culture and immunofluorescence analysis.Results: The rate of nodal metastasis was higher in patients with IMPC than those with IDC-NOS, and IMPC cells tended to express more sLe^(x) and MUC1/EMA in the cytomembranes(the stroma-facing surfaces of the micropapillary clusters) than IDC-NOS cells. In IMPC, high cytomembrane expression of sLe^(x), but not MUC1/EMA, indicated poor prognosis. In addition, among the 100 patients with IMPC, 10 patients had sLe^(x)+/EMA-expression patterns, and 8 patients had sLe^(x)-/EMA+ expression patterns. The primary IMPC cells were suspended, non-adherent tumor cell clusters, whereas the primary IDC cells were adherent tumor cells. Immunofluorescence analysis showed that MUC1/EMA and sLe^(x) were co-expressed on the cytomembranes in IMPC cell clusters and in the cytoplasm in IDC-NOS cells.Conclusions: sLe^(x) can be used as a prognostic indicator and can be combined with MUC1/EMA as a complementary diagnostic indicator to avoid missed IMPC diagnosis.Yawen Song Hui Sun Kailiang Wu Jianke Lyu Jingyue Zhang Feng Gu Yongjie Ma Beibei Shen Chijuan Wang Xiaojiao Chen Jing Xu Weidong Li Fangfang Liu Li Fu 2021Cancer Biology & Medicine2021,18,2:7
8Near-surface wind environment in the Yarlung Zangbo River basin,southern Tibetan Plateau显示文摘Aeolian processes have been studied extensively at low elevations,but have been relatively little studied at high elevations.Aeolian sediments are widely distributed in the Yarlung Zangbo River basin,southern Tibetan Plateau,which is characterized by low pressure and low temperature.Here,we comprehensively analyzed the wind regime using data since 1980 from 11 meteorological stations in the study area,and examined the interaction between the near-surface wind and aeolian environment.The wind environment exhibited significant spatial and temporal variation,and mean wind speed has generally decreased on both annual and seasonal bases since 1980,at an average of 0.181 m/(s•10a).This decrease resulted from the reduced contribution of maximum wind speed,and depended strongly on variations of the frequency of sand-driving winds.The drift potential and related parameters also showed obvious spatial and temporal variation,with similar driving forces for the wind environment.The strength of the wind regime affected the formation and development of the aeolian geomorphological pattern,but with variation caused by local topography and sediment sources.The drift potential and resultant drift direction were two key parameters,as they quantify the dynamic conditions and depositional orientation of the aeolian sediments.Wind affected the spatial variation in sediment grain size,but the source material and complex topographic effects on the near-surface wind were the underlying causes for the grain size distribution of aeolian sands.These results will support efforts to control aeolian desertification in the basin and improve our understanding of aeolian processes in high-elevation environments.YANG Junhuai XIA Dunsheng WANG Shuyuan TIAN Weidong MA Xingyue CHEN Zixuan GAO Fuyuan LING Zhiyong DONG Zhibao 2020Journal of Arid Land2020,12,6:5
9An experimental study of shear strength of gas-hydrate-bearing core samples显示文摘The shear strength of gas-hydrate-bearing reservoirs is one of the most important parameters used to study mechanical properties of gas-hydrate-bearing reservoirs.The shear strength of gas-hydratebearing reservoirs changes with filling and cementation of gas hydrates,which will affect the wellbore and reservoir stability.Traditional shear tests could not be conducted on gas-hydrate-bearing core samples because the gas hydrates exist under a limited range of temperature and pressure conditions.This paper describes a novel shear apparatus for studying shear strength of gas-hydrate-bearing core samples under original reservoir conditions.The preparation of gas-hydrate-bearing core samples and subsequent shear tests are done in the same cell.Cohesion and internal friction angle of the core samples with different saturations of gas hydrates were measured with the apparatus.The effect of gas hydrates on the shear strength of reservoirs was quantitatively analyzed.This provides a foundation for studying wellbore and reservoir stability of gas-hydrate-bearing reservoirs.Zhang Weidong Ma Qingtao Wang Ruihe Ren Shaoran 2011Petroleum Science2011,8,2:5
10Genome-wide CRISPR screen identifies synthetic lethality between DOCK1 inhibition and metformin in liver cancer显示文摘Metformin is currently a strong candidate anti-tumor agent in multiple cancers.However,its anti-tumor effectiveness varies among different cancers or sub-populations,potentially due to tumor heterogeneity.It thus remains unclear which hepatocellular carcinoma(HCC)patient subpopulation(s)can benefit from met-formin treatment.Here,through a genome-wide CRISPR-Cas9-based knockout screen,we find that DOCK1 levels determine the anti-tumor effects of met-formin and that DOCK1 is a synthetic lethal target of metformin in HCC.Mechanistically,metformin promotes DOCK1 phosphorylation,which activates RAC1 to facilitate cell survival,leading to metformin resistance.The DOCK1-selective inhibitor,TBOPP,potentiates anti-tumor activity by metformin in vitro in liver cancer cell lines and patient-derived HCC organoids,and in vivo in xenografted liver cancer cells and immunocompetent mouse liver cancer models.Notably,metformin improves overall survival of HCC patients with low DOCK1 levels but not among patients with high DOCK1 expression.This study shows that metformin effective-ness depends on DOCK1 levels and that combining metformin with DOCK1 inhibition may provide a promising personalized therapeutic strategy for met-formin-resistant HCC patients.Junru Feng Hui Lu Wenhao Ma Wenjing Tian Zhuan Lu Hongying Yang Yongping Cai Pengfei Cai Yuchen Sun Zilong Zhou Jiaqian Feng Jiazhong Deng Ying Shu Kun Qu Weidong Jia Ping Gao Huafeng Zhang 2022Protein & Cell2022,13,11:5
11Big data-enabled multiscale serviceability analysis for aging bridges显示文摘Yu Liang Dalei Wu Guirong Liu Yaohang Li Cuilan Gao Zhongguo John Ma Weidong Wu 2016Digital Communications and Networks2016,2,3:5
12Growth characteristics of spherical titanium oxide nanoparticles during the rapid gaseous detonation reaction显示文摘Ning Luo Hongwen Jing Zhanguo Ma Yingchao Wang Guilei Sun Weidong Liu 2016Particuology2016,14,3:4
13Auto-compensation of velocity-height ratio for Chang’E-2 satellite CCD stereo camera显示文摘The TDI-CCD imaging method using auto-compensation of velocity-height ratio (VHR) was applied to Chang’E-2 satellite CCD stereo camera.Factors that influence the image quality of the camera were discussed,among which the mismatch error in VHR was found to be the main cause.An auto-compensation scheme for VHR was developed.The validity and effectiveness were proved by the on-orbit high quality images.XUE Bin ZHAO BaoChang YANG JianFeng GAO Weit QIAO WeiDong MA XiaoLong ZHANG Bo LIU JiaHang ZHAO Wei JING Juan Juan 2011Science China(Technological Sciences)2011,54,9:4
14High-precision U-series dating of Holocene corals from South China Sea by thermal ionization mass spectrometry(TIMS)显示文摘Using the isotopic diluting and thermal ionization mass spectrometric (TIMS) technique, the U-series dating procedure was established on the basis of measurement of national standard GBW04412. With this highly precise technique the Holocene corals from the South China Sea were dated. Comparison between this method and α-spectrometry was made. The results show that a thriving period of corals in the South China Sea appeared at 6 800—5 800 a BP, during which the paleosea level was the higher than at present in the Holecene.Zhibang Ma Ming Xia Chenghui Zhang Zicheng Pen Zhaorong Wang Weidong Sun Zhisheng An 1999Chinese Science Bulletin1999,44,10:4
15High-performance flexible BiCMOS electronics based on single-crystal Si nanomembrane显示文摘In this work,we have demonstrated for the first time integrated flexible bipolar-complementary metal-oxide-semiconductor(BiCMOS)thin-film transistors(TFTs)based on a transferable single crystalline Si nanomembrane(Si NM)on a single piece of bendable plastic substrate.The n-channel,p-channel metal-oxide semiconductor field-effect transistors(N-MOSFETs&P-MOSFETs),and NPN bipolar junction transistors(BJTs)were realized together on a 340-nm thick Si NM layer with minimized processing complexity at low cost for advanced flexible electronic applications.The fabrication process was simplified by thoughtfully arranging the sequence of necessary ion implantation steps with carefully selected energies,doses and anneal conditions,and by wisely combining some costly processing steps that are otherwise separately needed for all three types of transistors.All types of TFTs demonstrated excellent DC and radio-frequency(RF)characteristics and exhibited stable transconductance and current gain under bending conditions.Overall,Si NM-based flexible BiCMOS TFTs offer great promises for high-performance and multifunctional future flexible electronics applications and is expected to provide a much larger and more versatile platform to address a broader range of applications.Moreover,the flexible BiCMOS process proposed and demonstrated here is compatible with commercial microfabrication technology,making its adaptation to future commercial use straightforward.Jung-Hun Seo Kan Zhang Munho Kim Weidong Zhou Zhenqiang Ma 2017npj Flexible Electronics2017,1,1:3
16Corrosion resistance and anti-soiling performance of micro-arc oxidation/graphene oxide/stearic acid superhydrophobic composite coating on magnesium alloys显示文摘Magnesium(Mg)alloys,the lightest metal construction material used in industry,play a vital role in future development.However,the poor corrosion resistance of Mg alloys in corrosion environments largely limits their potential wide applications.Therefore,a micro-arc oxidation/graphene oxide/stearic acid(MAO/GO/SA)superhydrophobic composite coating with superior corrosion resistance was fabricated on a Mg alloy AZ91D through micro-arc oxidation(MAO)technology,electrodeposition technique,and self-assembly technology.The composition and microstructure of the coating were characterized by scanning electron microscopy,X-ray diffraction,energy dispersive spectroscopy,and Raman spectroscopy.The effective protection of the MAO/GO/SA composite coating applied to a substrate was evaluated using potentiodynamic polarization,electrochemical impedance spectroscopy tests,and salt spray tests.The results showed that the MAO/GO/SA composite coating with a petal spherical structure had the best superhydrophobicity,and it attained a contact angle of 159.53°±2°.The MAO/GO/SA composite coating exhibited high resistance to corrosion,according to electrochemical and salt spray tests.Dong Wang Chen Ma Jinyu Liu Weidong Li Wei Shang Ning Peng Yuqing Wen 2023International Journal of Minerals,Metallurgy and Materials2023,30,6:3
17Porphyromonas gingivalis bacteremia increases the permeability of the blood-brain barrier via the Mfsd2a/Caveolin-1 mediated transcytosis pathway显示文摘Bacteremia induced by periodontal infection is an important factor for periodontitis to threaten general health. P. gingivalis DNA/virulence factors have been found in the brain tissues from patients with Alzheimer’s disease(AD). The blood-brain barrier(BBB) is essential for keeping toxic substances from entering brain tissues. However, the effect of P. gingivalis bacteremia on BBB permeability and its underlying mechanism remains unclear. In the present study, rats were injected by tail vein with P. gingivalis three times a week for eight weeks to induce bacteremia. An in vitro BBB model infected with P. gingivalis was also established. We found that the infiltration of Evans blue dye and Albumin protein deposition in the rat brain tissues were increased in the rat brain tissues with P. gingivalis bacteremia and P. gingivalis could pass through the in vitro BBB model. Caveolae were detected after P. gingivalis infection in BMECs both in vivo and in vitro. Caveolin-1(Cav-1) expression was enhanced after P. gingivalis infection.Downregulation of Cav-1 rescued P. gingivalis-enhanced BMECs permeability. We further found P. gingivalis-gingipain could be colocalized with Cav-1 and the strong hydrogen bonding between Cav-1 and arg-specific-gingipain(RgpA) were detected.Moreover, P. gingivalis significantly inhibited the major facilitator superfamily domain containing 2a(Mfsd2a) expression. Mfsd2a overexpression reversed P. gingivalis-increased BMECs permeability and Cav-1 expression. These results revealed that Mfsd2a/Cav-1 mediated transcytosis is a key pathway governing BBB BMECs permeability induced by P. gingivalis, which may contribute to P. gingivalis/virulence factors entrance and the subsequent neurological impairments.Shuang Lei Jian Li Jingjun Yu Fulong Li Yaping Pan Xu Chen Chunliang Ma Weidong Zhao Xiaolin Tang 2023International Journal of Oral Science2023,15,1:3
18Water in coesite: Incorporation mechanism and operation condition,solubility and P-T dependence, and contribution to water transport and coesite preservation显示文摘A series of coesite,coexisting with or without a liquid phase,was synthesized in the nominal system SiO2-H2O at800-1450℃and 5 GPa.Micro-Raman spectroscopy was used to identity the crystalline phase,electron microprobe and LA-ICP-MS were employed to quantity some major and trace elements,and unpolarized FTIR spectroscopy was applied to probe the different types of hydrogen defects,explore water-incorporation mechanisms and quantify water contents.Trace amounts of A1 and B were detected in the coesite.Combining our results with the results in the literatures,we have found no positive correlation between the Al contents and the'Al'-based hydrogen concentrations,suggesting that previously proposed hydrogen-incorporation mechanism H^++Al^3+■Si^4+does not function in coesite.In contrast,we have confirmed the positive correlation between the B contents and the B-based hydrogen concentrations.The hydrogen-incorporation mechanism H^++B3^+■Si^4+readily takes place in coesite at different P-T conditions,and significantly increases the water content at both liquid-saturated and liquid-undersaturated conditions.For the SiO2-H2O system,we have found that type-Ⅰhydrogarnet substitution plays a dictating role in incorporating water into coesite at liquid-saturated condition,type-II hydrogarnet substitution contributes significantly at nearly dry condition,and both operate at conditions in between.The water solubility of coesite,as dictated by the type-Ⅰhydrogarnet substitution,positively correlates with both P and T,cH2O=-105(30)+5.2(32)×P+0.112(26)×T,with cH2O in wt ppm,P in GPa and T in℃.Due to its low water solubility and small fraction in subducted slabs,coesite may contribute insignificantly to the vertical water transport in subduction zones.Furthermore,the water solubility of any coesite in exhuming ultra-high pressure metamorphic rocks should be virtually zero as coesite becomes metastable.With an adequately fast waterdiffusion rate,this metastable coesite should be completely dry,which may have been the key factor to the partial preservation of most natural Coe.As a byproduct,a new IR experimental protocol for accurate water determination in optically anisotropic nominally anhydrous minerals has been found.Aided with the empirical method of Paterson(1982)it employs multiple unpolarized IR spectra,collected from randomly-orientated mineral grains,to approximate both total integrated absorbance and total integrated molar absorption coefficient.Its success relies on a high-level orientation randomness in the IR analyses.Wei Yan Yanyao Zhang Yunlu Ma Mingyue He Lifei Zhang Weidong Sun Christina Yan Wang Xi Liu 2021Geoscience Frontiers2021,12,1:3
19Characterization of the hot deformation behavior of a Ti–22Al–25Nb alloy using processing maps based on the Murty criterion显示文摘Xiong Ma Weidong Zeng Bin Xu Yu Sun Chen Xue Yuanfei Han 2011Intermetallics2011,,1:3
20Microstructural evolution and enhanced mechanical properties of Mg?Gd?Y?Zn?Zr alloy via centrifugal casting, ring-rolling and aging显示文摘A ring-shaped Mg?8.5 Gd?4 Y?1 Zn?0.4 Zr(wt%) alloy was manufactured via centrifugal casting and ring-rolling process. The effects of accumulative ring-rolling reduction amount on the microstructure, texture, and tensile properties of the alloy were investigated. The results indicate that the microstructure of centrifugal cast alloy consists of equiaxed grains and network-like eutectic structure present at grain boundaries. The ring-rolled alloy exhibits a characteristic bimodal microstructure composed of fine dynamic recrystallized(DRXed) grains with weak basal texture and coarse un-DRXed grains with strong basal texture, along with the presence of LPSO phase. With increasing amount of accumulative ring-rolling reduction, the coarse un-DRXed grains are refined via the formation of increasing amount of fine DRXed grains. Meanwhile, the dynamic precipitation of Mg5 RE phase occurs, generating a dispersion strengthening effect. A superior combination of strength and ductility is achieved in the ring-rolled alloy after an accumulative rolling reduction of 80%. The tensile strength of this ring-rolled alloy after peak aging is further enhanced, reaching 511 MPa, while keeping a reasonable ductility. The salient strengthening mechanisms identified include the grain boundary strengthening of fine DRXed grains, dispersion strengthening of dynamic precipitated Mg;RE phase, short fiber strengthening of LPSO lamellae/rods, and precipitation strengthening of nano-sized prismatic β precipitates and basal γ precipitates.Zhenduo Ma Guo Li Qiang Peng Xiaodong Peng Daolun Chen HanzhuZhang Yan Yang Guobing Wei Weidong Xie 2022Journal of Magnesium and Alloys2022,10,1:3
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