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A virtual thermometer for ultrahigh-temperature-pressure experiments in a large-volume press

Matter and Radiation at Extremes 2024年第4期9卷 98-110页

作者： Bingtao Feng Longjian Xie Xuyuan Hou Shucheng Liu Luyao Chen Xinyu Zhao Chenyi Li Qiang Zhou kuo hu Zhaodong Liu Bingbing Liu State Key Laboratory of Superhard Materials Synergetic Extreme Condition User FacilityCollege of PhysicsJilin UniversityChangchun 130012China Department of Earth Sciences University College LondonLondon WC1E 6BSUnited Kingdom Earth and Planetary Laboratory Carnegie Institute for ScienceWashingtonDistrict of Columbia 20015USA College of Earth Sciences Jilin UniversityChangchun 130012China

Ultrahigh-temperature-pressure experiments are crucial for understanding the physical and chemical properties of *** recent development of boron-doped diamond(BDD)heaters has made such melting experiments possible in large-volume ***,estimates of temperatures above 2600 K and of the temperature distributions inside BDD heaters are not well constrained,owing to the lack of a suitable ***,we establish a three-dimensional finite element model as a virtual thermometer to estimate the temperature and temperature field above 2600 *** advantage of this virtual thermometer over those proposed in previous studies is that it considers both alternating and direct current heating modes,the actual sizes of cell assemblies after compression,the effects of the electrode,thermocouple and anvil,and the heat dissipation by the pressure-transmitting *** virtual thermometer reproduces the power-temperature relationships of ultrahigh-temperature-pressure experiments below 2600 K at press loads of 2.8-7.9 MN(~19 to 28 GPa)within experimental *** temperatures above 2600 K predicted by our virtual thermometer are within the uncertainty of those extrapolated from power-temperature relationships below 2600 ***,our model shows that the temperature distribution inside a BDD heater(19-26 K/mm along the radial direction andhus provides a reliable virtual thermometer for ultrahigh-temperature experiments using BDD heaters in Earth and material sciences.

关键词： virtual ultrahigh sizes

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Cellular and molecular overview of gestational diabetes mellitus:Is it predictable and preventable?

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World Journal of Diabetes 2023年第11期14卷 1693-1709页

作者： Pei-Qi Lim Yen-Ju Lai Pei-Ying Ling kuo-hu Chen Department of Obstetrics and Gynecology Taiwan Adventist HospitalTaipei 105TaiwanChina School of Medicine George Washington UniversityWashingtonDC 20052United States Department of Obstetrics and Gynecology Taipei Tzu-Chi General HospitalTaipei 231TaiwanChina

BACKGROUND In contrast to overt diabetes mellitus(DM),gestational DM(GDM)is defined as impaired glucose tolerance induced by pregnancy,which may arise from exaggerated physiologic changes in glucose *** prevalence is reported to be as high as 20%among pregnancies depending on the screening method,gestational age,and the population *** and fetal effects of uncontrolled GDM include stillbirth,macrosomia,neonatal diabetes,birth trauma,and subsequent postpartum ***,it is essential to find the potential target population and associated predictive and preventive measures for future intensive peripartum *** To review studies that explored the cellular and molecular mechanisms of GDM as well as predictive measures and prevention *** The search was performed in the Medline and PubMed databases using the terms“gestational diabetes mellitus,”“overt diabetes mellitus,”and“insulin resistance.”In the literature,only full-text articles were considered for inclusion(237 articles).Furthermore,articles published before 1997 and duplicate articles were *** a final review by two experts,all studies(1997-2023)included in the review met the search terms and search strategy(identification from the database,screening of the studies,selection of potential articles,and final inclusion).RESULTS Finally,a total of 79 articles were collected for *** risk factors for GDM included maternal obesity or overweight,pre-existing DM,and polycystic ovary *** pathophysiology of GDM involves genetic variants responsible for insulin secretion and glycemic control,pancreaticβcell depletion or dysfunction,aggravated insulin resistance due to failure in the plasma membrane translocation of glucose transporter 4,and the effects of chronic,low-grade ***,many antepartum measurements including adipokines(leptin),body mass ratio(waist circumference and waist-to-hip ratio),and biomarkers(microRNA in extra

关键词： Gestational diabetes mellitus Overt diabetes mellitus Insulin resistance Diabetes mellitus

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大腔体压机腔体压强28 GPa的标定方法

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高压物理学报 2024年第3期38卷 121-128页

作者：葛雨非由存王星淋连敏赵鑫宇丰丙涛马孝慈陶强胡阔刘兆东周强朱品文吉林大学物理学院超硬材料国家重点实验室综合极端条件高压科学中心吉林长春130012

在大腔体压机中,一般利用压标物质相变时的电阻变化进行腔体压强标定,但目前仍缺少在22.5~34.5 GPa区间的相变压标物质。地球深部矿物50%MgSiO_(3)-_(50)%Al_(2)O_(3)(En_(50)Cor_(50))在高温高压下转变为钙钛矿结构,且在27 GPa以上钙... 详细信息

在大腔体压机中,一般利用压标物质相变时的电阻变化进行腔体压强标定,但目前仍缺少在22.5~34.5 GPa区间的相变压标物质。地球深部矿物50%MgSiO_(3)-_(50)%Al_(2)O_(3)(En_(50)Cor_(50))在高温高压下转变为钙钛矿结构,且在27 GPa以上钙钛矿结构MgSiO_(3)中溶解的Al_(2)O_(3)含量随压力升高而增加。为此,选取En_(50)Cor_(50)作为大腔体压机中28 GPa的压标物质进行高压腔体压强的间接标定。首先,利用常用压标物质的相变进行腔体压强标定,得到低压区系统油压-腔体压强的校正曲线(6.0~22.5 GPa);随后,根据低压区校正曲线及前人对En_(50)Cor_(50)的研究结果,估算28 GPa腔体压强对应的系统油压;将En_(50)Cor_(50)在预估油压、2000 K温度条件下保温3~7 h;最后,利用X射线衍射、拉曼光谱、电子探针等手段对En_(50)Cor_(50)进行测试分析。结果表明:在该条件下成功合成了布里奇曼石,且Al2O_(3)的溶解度大于13.7%,对照前人的研究结果,确定样品腔体压强约为29 GPa。该方法成功标定了大腔体压机在28 GPa附近的腔体压强,填补了大腔体压机在该压强范围的标定空白。

关键词：大腔体压机压力标定 28 GPa 高温高压

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Dietary sodium acetate and sodium butyrate attenuate intestinal damage and improve lipid metabolism in juvenile largemouth bass(Micropterus salmoides) fed a high carbohydrate diet by reducing endoplasmic reticulum stress

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Animal Nutrition 2024年第1期16卷 443-456页

作者： Liulan Zhao Liangshun Cheng Yifang hu Xiaohui Li Yihui Yang Jin Mu Lianfeng Shen Guojun hu kuo He Haoxiao Yan Qiao Liu Song Yang College of Animal Science and Technology Sichuan Agricultural University

High-carbohydrate(HC) diets decrease the intestinal levels of sodium acetate(SA) and sodium butyrate(SB) and impair the gut health of largemouth bass; however, SA and SB have been shown to enhance immunity and improve intestinal health in farmed animals. Thus, the present study was to investigate the effects of dietary SA and SB on HC diet-induced intestinal injury and the potential mechanisms in juvenile largemouth bass. The experiment set five isonitrogenous and isolipidic diets, including a lowcarbohydrate diet(9% starch)(LC), a high carbohydrate diet(18% starch)(HC), and the HC diet supplemented with 2 g/kg SA(HCSA), 2 g/kg SB(HCSB) or a combination of 1 g/kg SA and 1 g/kg SB(HCSASB).The feeding experiment was conducted for 8 weeks. A total of 525 juvenile largemouth bass with an initial body weight of 7.00 ± 0.20 g were used. The results showed that dietary SA and SB improved the weight gain rate and specific growth rate (P<0.05) and ameliorated serum parameters(alkaline phosphatase, acid phosphatase, glutamate transaminase, and glutamic oxaloacetic transaminase)(P<0.05). And, importantly, dietary SA and SB repaired the intestinal barrier by increasing the expression levels of zonula occludens-1, occludin, and claudin-7(P<0.05), reduced HC-induced intestinal damage, and alleviated intestinal inflammation and cell apoptosis by attenuating HC-induced intestinal endoplasmic reticulum stress(P<0.05). Further results revealed that dietary SA and SB reduced HC-induced intestinal fat deposition by inhibiting adipogenesis and promoting lipolysis(P<0.05). In summary, this study demonstrated that dietary SA and SB attenuated HC-induced intestinal damage and reduced excessive intestinal fat deposition in largemouth bass.

关键词： Sodium acetate Sodium butyrate High carbohydrate diet Endoplasmic reticulum stress Intestine health Lipid metabolism

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Flexible nanoimprint lithography enables high-throughput manufacturing of bioinspired microstructures on warped substrates for efficient III-nitride optoelectronic devices

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Science Bulletin 2024年第13期69卷 2080-2088页

作者： Siyuan Cui Ke Sun Zhefu Liao Qianxi Zhou Leonard Jin Conglong Jin Jiahui hu kuo-Sheng Wen Sheng Liu Shengjun Zhou Center for Photonics and Semiconductors School of Power and Mechanical EngineeringWuhan UniversityWuhan 430072China The Institute of Technological Sciences Wuhan UniversityWuhan 430072China Department of Mechanical and Mechatronics Engineering University of WaterlooWaterloo ONN2L 3G1Canada Jiangxi SMTC Semiconductor Co. Ltd.Nanchang 330096China

III-nitride materials are of great importance in the development of modern optoelectronics,but they have been limited over years by low light utilization rate and high dislocation densities in heteroepitaxial films grown on foreign substrate with limited refractive index contrast and large lattice ***,we demonstrate a paradigm of high-throughput manufacturing bioinspired microstructures on warped substrates by flexible nanoimprint lithography for promoting the light extraction *** design a flexible nanoimprinting mold of copolymer and a two-step etching process that enable high-efficiency fabrication of nanoimprinted compound-eye-like Al2O3 microstructure(NCAM)and nanoimprinted compound-eye-like SiO_(2)microstructure(NCSM)template,achieving a 6.4-fold increase in throughput and 25%savings in economic costs over stepper projection *** to NCAM template,we find that the NCSM template can not only improve the light extraction capability,but also modulate the morphology of AlN nucleation layer and reduce the formation of misoriented GaN grains on the inclined sidewall of microstructures,which suppresses the dislocations generated during coalescence,resulting in 40%reduction in dislocation *** study provides a low-cost,high-quality,and high-throughput solution for manufacturing microstructures on warped surfaces of III-nitride optoelectronic devices.

关键词： Flexible nanoimprint lithography Bioinspired Micro-and nano-manufacturing III-nitride epitaxy Optoelectronic devices

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Dietary sodium acetate and sodium butyrate improve high-carbohydrate diet utilization by regulating gut microbiota, liver lipid metabolism, oxidative stress, and inflammation in largemouth bass(Micropterus salmoides)

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Journal of Animal Science and Biotechnology 2024年第4期15卷 1704-1722页

作者： Qiao Liu Liangshun Cheng Maozhu Wang Lianfeng Shen Chengxian Zhang Jin Mu Yifan hu Yihui Yang kuo He Haoxiao Yan Liulan Zhao Song Yang College of Animal Science and Technology Sichuan Agricultural UniversityChengdu 611130SichuanChina

Background Adequate level of carbohydrates in aquafeeds help to conserve protein and reduce cost. However, studies have indicated that high-carbohydrate(HC) diet disrupt the homeostasis of the gut–liver axis in largemouth bass, resulting in decreased intestinal acetate and butyrate *** Herein, we had concepted a set of feeding experiment to assess the effects of dietary sodium acetate(SA) and sodium butyrate(SB) on liver health and the intestinal microbiota in largemouth bass fed an HC diet. The experimental design comprised 5 isonitrogenous and isolipidic diets, including LC(9% starch), HC(18% starch), HCSA(18% starch;2 g/kg SA), HCSB(18% starch;2 g/kg SB), and HCSASB(18% starch;1 g/kg SA + 1 g/kg SB). Juvenile largemouth bass with an initial body weight of 7.00 ± 0.20 g were fed on these diets for 56 *** We found that dietary SA and SB reduced hepatic triglyceride accumulation by activating autophagy(ATG101, LC3B and TFEB), promoting lipolysis(CPT1α, HSL and AMPKα), and inhibiting adipogenesis(FAS, ACCA, SCD1 and PPARγ). In addition, SA and SB decreased oxidative stress in the liver(CAT, GPX1α and SOD1) by activating the Keap1-Nrf2 pathway. Meanwhile, SA and SB alleviated HC-induced inflammation by downregulating the expression of pro-inflammatory factors(IL-1β, COX2 and Hepcidin1) through the NF-κB pathway. Importantly, SA and SB increased the abundance of bacteria that produced acetic acid and butyrate(Clostridium_sensu_stricto_1). Combined with the KEGG analysis, the results showed that SA and SB enriched carbohydrate metabolism and amino acid metabolism pathways, thereby improving the utilization of carbohydrates. Pearson correlation analysis indicated that growth performance was closely related to hepatic lipid deposition, autophagy, antioxidant capacity, inflammation, and intestinal microbial *** In conclusion, dietary SA and SB can reduce hepatic lipid deposition;and alleviate oxidative stress and inflammation in largemout

关键词： High carbohydrate diet Intestinal microbiota Largemouth bass Lipid deposition Sodium acetate Sodium butyrate

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Benchmark experiment on slab^(238)U with D-T neutrons for validation of evaluated nuclear data

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Nuclear Science and Techniques 2024年第2期35卷 145-159页

作者： Yan-Yan Ding Yang-Bo Nie Yue Zhang Zhi-Jie hu Qi Zhao huan-Yu Zhang kuo-Zhi Xu Shi-Yu Zhang Xin-Yi Pan Chang-Lin Lan Jie Ren Xi-Chao Ruan Key Laboratory of Nuclear Data China Institute of Atomic EnergyBeijing 102413China School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China Institute of Fluid Physics China Academy of Engineering PhysicsMianyang 62100China

A benchmark experiment on^(238)U slab samples was conducted using a deuterium-tritium neutron source at the China Institute of Atomic *** leakage neutron spectra within energy levels of 0.8-16 MeV at 60°and 120°were measured using the time-of-flight *** samples were prepared as rectangular slabs with a 30 cm square base and thicknesses of 3,6,and 9 *** leakage neutron spectra were also calculated using the MCNP-4C program based on the latest evaluated files of^(238)U evaluated neutron data from CENDL-3.2,ENDF/B-Ⅷ.0,JENDL-5.0,and *** on the comparison,the deficiencies and improvements in^(238)U evaluated nuclear data were *** results showed the following.(1)The calculated results for CENDL-3.2 significantly overestimated the measurements in the energy interval of elastic scattering at 60°and 120°.(2)The calculated results of CENDL-3.2 overestimated the measurements in the energy interval of inelastic scattering at 120°.(3)The calculated results for CENDL-3.2 significantly overestimated the measurements in the 3-8.5 MeV energy interval at 60°and 120°.(4)The calculated results with JENDL-5.0 were generally consistent with the measurement results.

关键词： Leakage neutron spectra Uranium D-T neutron source Evaluated nuclear data

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高压导致纳米TiO_(2)形变的电子显微研究

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物理学报 2023年第3期72卷 207-214页

作者：王飞李全军胡阔刘冰冰吉林大学超硬材料国家重点实验室长春130012

α-PbO_(2)相TiO_(2)高压相具有适宜的带隙能和可见光范围的光催化能力,是一种适用于可见光、高效且环保的光催化材料.本文使用金刚石对顶压砧对锐钛矿纳米球进行加压-卸压处理得到了α-PbO_(2)相TiO_(2)高压相.利用透射电子显微镜对比... 详细信息

α-PbO_(2)相TiO_(2)高压相具有适宜的带隙能和可见光范围的光催化能力,是一种适用于可见光、高效且环保的光催化材料.本文使用金刚石对顶压砧对锐钛矿纳米球进行加压-卸压处理得到了α-PbO_(2)相TiO_(2)高压相.利用透射电子显微镜对比初始样品和卸压样品,观察结果表明晶粒发生了明显形变,高分辨图显示其晶粒中存在大量[100]方向层错和形变孪晶,其中亚微米级晶粒中形成了透镜形片层结构的形变孪晶带;纳米级晶粒中形成了扇形多重形变孪晶.研究表明高压下锐钛矿TiO_(2)可以发生明显的形变,其形变的微观机制与金属类似,主要为形变孪晶和层错滑移,形变孪晶的形成存在明显的尺寸效应.这些结果为TiO_(2)高压相变的尺寸效应研究提供了一个新的切入点,同时还为制备孪晶α-PbO_(2)相TiO_(2)高压相提供了方法.

关键词：高压 a-PbO_(2)相TiO_(2) 形变孪晶尺寸效应

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LiOH-mediated crystallization regulating strategy enhancing electrochemical performance and structural stability of SiO anodes for lithium-ion batteries

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Nano Research 2024年第9期17卷 8174-8183页

作者： Zhengqiu He Zewen Xu Yu Long Jiexin Zhu Hao Yang kuo Chen Qiang Zhou Ning Cao Xiaobo Wang Juan Wang Xiaojie Tan Litao Wang Luhai Wang Shengbao He Mengdi Zhang Han hu Mingbo Wu State Key Laboratory of Heavy Oil Processing College of Chemistry and Chemical EngineeringChina University of Petroleum(East China)Qingdao 266580China Department of Chemistry National University of Singapore3 Science Drive 3Singapore 117543Singapore School of Chemical Sciences University of AucklandAuckland 1010New Zealand Petrochemical Research Institute Petro China Company Ltd.Beijing 102206China

Silicon monoxide(SiO)is widely recognized as a promising anode material for next-generation lithium-ion *** to its metastable amorphous structure,SiO exhibits a highly complex degree of crystallization at the microscopic level,which significantly influences its electrochemical *** a consequence,accurately regulating the crystallization of SiO,and further establishing the relationship between crystallinity and electrochemical performance are very critical for SiO *** this article,carbon-coated SiO materials with different crystallinity degrees were synthesized using lithium hydroxide monohydrate(LiOH·H_(2)O)as a structural modifier to reveal this ***,moderate amount of LiOH·H_(2)O addition results in the forming of an oxygen-rich shell,which effectively inhibits the inward migration of oxygen atoms on the SiO surface and suppresses volume ***,the crystallinity of SiO will gradually enhance and the crystalline phase appears with increasing the amount of LiOH·H_(2)O,which will generate a deteriorative Li+diffusion *** balancing the above two contradictions,a mass fraction of 1%LiOH·H_(2)O for the additive yielded SiO@C-1,characterized by optimal ***@C-1 demonstrates exceptional long-cycle stability with 74.8%capacity retention after 500 cycles at 1 A·g^(-1).Furthermore,it achieves a capacity retention of 52.2%even at a high density of 5 A·g^(-1).This study first reveals the relationship between SiO crystallinity and electrochemical performance,which efficiently guides the design of high-performance SiO anodes.

关键词： lithium-ion batteries SiO anodes crystallinity regulation high rate long life

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基于变载波频率的永磁同步电机驱动系统效率优化控制

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东南大学学报（自然科学版） 2024年第3期54卷 724-729页

作者：刘凯张阔花为胡铭觐东南大学电气工程学院南京210096

为降低永磁同步电机驱动系统的损耗,提高系统效率,提出了一种基于母线电流反馈的变载波频率优化控制方法.首先,建立了系统损耗数学模型,探究了载波频率与系统损耗的关系.然后,针对离线优化方法对于参数敏感的问题,设计了一种基于母线电... 详细信息

为降低永磁同步电机驱动系统的损耗,提高系统效率,提出了一种基于母线电流反馈的变载波频率优化控制方法.首先,建立了系统损耗数学模型,探究了载波频率与系统损耗的关系.然后,针对离线优化方法对于参数敏感的问题,设计了一种基于母线电流反馈的载波频率在线寻优方法.结果表明,在不同转速与负载条件下均存在使系统损耗最小的最优载波频率,其随转速与负载条件变化而变化.在各个工作点,系统损耗的计算值均与实测值基本吻合.在线寻优方法在中高负载情况下能够实现约0.6%的效率优化,并且在负载变化的情况下仍然能够实现损耗优化.

关键词：变载波频率损耗模型效率优化永磁同步电机

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