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Continuous SiC skeleton reinforced highly oriented graphite flake composites with high strength and specific thermal conductivity

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Journal of Advanced Ceramics 2022年第3期11卷 403-413页

作者： Xiaoyu zhang Wenqi XIE Lan SUN Zhilei WEI zhejian zhang Yuanyuan ZHU Jiabin HU Shenghe WANG Zhongqi SHI State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong UniversityXi’an710049China State Grid Anhui Electric Power Co. Ltd.Hefei230061China

Highly oriented graphite-based composites have attracted great attention because of their high thermal conductivity(TC),but the low mechanical properties caused by the inhomogeneous distribution and discontinuity of reinforcements restrict the wide ***,continuous SiC ceramic skeleton reinforced highly oriented graphite flake(SiC/GF)composites were successfully prepared by combining vacuum filtration and spark plasma *** effect of SiC concentration on the microstructure,flexural strength,and thermophysical properties of the composites was *** GF grains in the composites exhibited high orientation with a Lotgering factor of>88%when the SiC concentration was≤30 wt%,and the SiC skeleton became continuous with the SiC concentration reaching 20 wt%.The formation of continuous SiC skeleton improved the flexural strength of the composites effectively while keeping the TC in a high ***,the composites with 30 wt%SiC exhibited the flexural strength up to 105 MPa,and the specific TC reaching 0.118 W·m^(2)·K^(−1)·*** composites with excellent flexural strength and thermophysical properties showed significant promise for thermal management applications.

关键词： ceramics composite materials high orientation flexural strength heat conduction

Preparation and anisotropic thermophysical properties of SiC honeycomb/Al-Mg-Si composite via spontaneous infiltration

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Progress in Natural Science:Materials International 2019年第2期29卷 177-183页

作者： zhejian zhang Zhongqi Shi Biguo Yang Bangzhi Ge Xiaoyu zhang Yajie Guo State Key Laboratory for Mechanical Behavior of Materials Xi'an Jiaotong University Engineering Research Center of Transportation Materials of Ministry of Education School of Materials Science and Engineering Chang'an University

The SiC honeycomb/Al-Mg-Si composite with interpenetrated microstructure was prepared by spontaneous infiltration of Al-8 wt%Mg-7 wt%Si alloy into directional porous SiC honeycomb served as reinforcement. The microstructure and anisotropic thermophysical properties of this composite were also examined. The results showed that the initial microstructure of the SiC honeycomb can be retained and the as-prepared SiC honeycomb/Al-Mg-Si composite exhibited significantly anisotropic characteristics. Meanwhile, the alloying treatment on the Al matrix can avoid the generation of Al;C;and promote the wettability between Al and ***,the directional porous SiC honeycomb with such a low ceramic content（19 vol.%） made it possible for the composite to have a higher thermal conductivity(138.3 W/（m?K）) in the axial direction and a lower coefficient of thermal expansion(11.40 × 10;/K) in the radial *** influences of the SiC honeycomb reinforcement on the anisotropic thermophysical properties were also studied by the theoretical models in comparing with the experimental results.

关键词： SiC honeycomb Al-Mg-Si alloy Spontaneous infiltration Anisotropy Thermophysical properties

MOSS:An Open Conversational Large Language Model

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Machine Intelligence Research 2024年第5期21卷 888-905页

作者： Tianxiang Sun Xiaotian zhang Zhengfu He Peng Li Qinyuan Cheng Xiangyang Liu Hang Yan Yunfan Shao Qiong Tang Shiduo zhang Xingjian Zhao Ke Chen Yining Zheng zhejian Zhou Ruixiao Li Jun Zhan Yunhua Zhou Linyang Li Xiaogui Yang Lingling Wu zhangyue Yin Xuanjing Huang Yu-Gang Jiang Xipeng Qiu Fudan University Shanghai200438China

Conversational large language models(LLMs)such as ChatGPT and GPT-4 have recently exhibited remarkable capabilities across various domains,capturing widespread attention from the *** facilitate this line of research,in this paper,we report the development of MOSS,an open-sourced conversational LLM that contains 16 B parameters and can perform a variety of instructions in multi-turn interactions with *** base model of MOSS is pre-trained on large-scale unlabeled English,Chinese,and code *** optimize the model for dialogue,we generate 1.1 M synthetic conversations based on user prompts collected through our earlier versions of the model *** then perform preference-aware training on preference data annotated from AI *** results on real-world use cases and academic benchmarks demonstrate the effectiveness of the proposed *** addition,we present an effective practice to augment MOSS with several external *** the development of MOSS,we have established a complete technical roadmap for large language models from pre-training,supervised fine-tuning to alignment,verifying the feasibility of chatGPT under resource-limited conditions and providing a reference for both the academic and industrial *** weights and code are publicly available at https://***/OpenMOSS/MOSS.

关键词： Large language models natural language processing pre-training alignment chatGPT MOSS

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单站水下方位频率机动目标运动分析方法

声学学报 2024年第4期49卷 683-695页

作者：孙大军张艺翱滕婷婷胡哲健哈尔滨工程大学水声技术全国重点实验室哈尔滨150001 工业和信息化部海洋信息获取与安全工信部重点实验室(哈尔滨工程大学) 哈尔滨150001 哈尔滨工程大学水声工程学院哈尔滨150001

水下方位频率机动目标运动分析常需已知中心频率先验信息且存在机动检测错误等,因此提出了一种基于方位与多线谱信息融合的自适应无迹卡尔曼滤波算法。该算法将方位与多线谱频率信息融合处理,重新构建了方位−多线谱目标运动分析模型。... 详细信息

水下方位频率机动目标运动分析常需已知中心频率先验信息且存在机动检测错误等,因此提出了一种基于方位与多线谱信息融合的自适应无迹卡尔曼滤波算法。该算法将方位与多线谱频率信息融合处理,重新构建了方位−多线谱目标运动分析模型。将中心频率信息引入状态向量中构建实时迭代估计,同时引入了自适应时变渐消因子,实时调整过程噪声协方差矩阵使其适应机动目标。仿真与海试数据处理结果表明,所提方法的机动目标运动分析性能最优,其目标运动分析结果能以最快的速度逼近克拉美罗下界。

关键词：目标运动分析多线谱信息融合机动目标跟踪无迹卡尔曼滤波渐消因子

弥散加权成像Alberta卒中项目早期CT评分评估急性前循环脑梗死静脉溶栓预后的价值

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中华老年心脑血管病杂志 2018年第1期20卷 60-63页

作者：张江王瑶张喆鉴华北理工大学附属医院神经内科二病区唐山063000 华北理工大学研究生学院西交利物浦大学计算机科学与技术系

目的探讨磁共振弥散加权成像Alberta卒中项目早期CT评分(DWI-ASPECTS)对急性前循环脑梗死静脉溶栓治疗预后的预测价值。方法选择接受静脉溶栓的急性前循环脑梗死患者99例,根据溶栓3个月后改良的Rankin量表(mRS)评分分为2组,mRS评分0~2... 详细信息

目的探讨磁共振弥散加权成像Alberta卒中项目早期CT评分(DWI-ASPECTS)对急性前循环脑梗死静脉溶栓治疗预后的预测价值。方法选择接受静脉溶栓的急性前循环脑梗死患者99例,根据溶栓3个月后改良的Rankin量表(mRS)评分分为2组,mRS评分0~2分为良好转归组66例,3~6分为不良转归组33例。收集患者的一般临床资料、DWI-ASPECTS评分、溶栓3个月后mRS、溶栓3个月后改良的Barthel指数(MBI)以及并发症情况。结果与不良转归组比较,良好转归组年龄和入院美国国立卫生研究院卒中量表(NIHSS)评分显著降低,DWI-ASPECTS评分显著升高(P<0.05)。logistic回归分析显示,年龄(OR=1.097,95%CI:1.019~1.180,P=0.013)、入院NIHSS评分(OR=1.207,95%CI:1.025~1.421,P=0.024)、DWI-ASPECTS评分(OR=0.543,95%CI:0.343~0.858,P=0.009)是不良转归发生的独立预测因素。DWI-ASPECTS评分曲线下面积为0.887(95%CI:0.822~0.951),预测不良转归的最佳临界点为5.5,敏感性为84.8%,特异性为81.8%。DWI-ASPECTS评分与MBI呈正相关(P=0.000)。列联分析显示,DWI-ASPECTS评分与血管再闭塞、出血、缺血再灌注损伤存在相关性(P<0.01)。结论 DWI-ASPECTS评分是评估急性前循环脑梗死患者静脉溶栓治疗预后转归的重要指标。

关键词：磁共振成像弥散脑梗死再灌注损伤预后

Unveiling the mechanism of yttrium significantly improving high-temperature oxidation resistance of super-austenitic stainless steel S32654

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Journal of Materials Science & Technology 2022年第20期115卷 103-114页

作者： Shucai zhang Huabing Li Zhouhua Jiang Hao Feng zhejian Wen Junyu Ren Peide Han School of Metallurgy Northeastern UniversityShenyang 110819China Key Laboratory for Ecological Metallurgy of Multimetallic Ores(Ministry of Education) Shenyang 110819China College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China

Aiming at serious catastrophic oxidation problem of super-austenitic stainless steel S32654,the influence of different rare earth elements on its oxidation behavior was comparatively investigated at 1200℃.The mechanism of Y significantly improving high-temperature oxidation resistance of S32654 was *** results demonstrated that Y played much better beneficial roles than Ce and La in the initial formation of oxide layer:(1)Y promoted Cr segregation to steel surface to combine with O;(2)its preferential oxidation provided nucleation cores for Cr_(2)O_(3).Both roles jointly promoted the selective oxidation of Cr and then the formation of protective Cr-rich oxide *** provided good prerequisites for inhibiting the formation and volatilization of MoO_(3).Additionally,Y cation segregation to oxide grain boundaries further promoted the selective oxidation of Cr and Si to form more protective oxide *** beneficial roles of Y essentially eliminated the synergistic effects of MoO_(3) volatilization and lamellar Cr_(2)N precipitation on catastrophic ***,the oxidation resistance of Y-bearing S32654 was improved by 22%–45%.

关键词： Super-austenitic stainless steel Rare earth elements Yttrium Oxidation MoO_(3)volatilization Cr_(2)N precipitation

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北洺河铁矿回风井直角弯的模拟改造

矿业研究与开发 2016年第9期36卷 65-68页

作者：郭鑫禾高晓明陈立张哲健河北工程大学资源学院河北邯郸市056038 河北省煤炭矿井建设工程技术研究中心河北邯郸市056038 北京科技大学土木与环境工程学院北京100083

为减小北洺河铁矿―50^+5m回风井两个直角转弯造成的局部通风阻力,对其巷道进行模拟降阻改造。基于对此回风巷通风参数的实测数据,借助Gambit建立此回风巷模型并划分网格,使用Fluent软件分析直角弯处的风流压力和速度分布情况,然后基于... 详细信息

为减小北洺河铁矿―50^+5m回风井两个直角转弯造成的局部通风阻力,对其巷道进行模拟降阻改造。基于对此回风巷通风参数的实测数据,借助Gambit建立此回风巷模型并划分网格,使用Fluent软件分析直角弯处的风流压力和速度分布情况,然后基于分析结果对直角弯进行改造,再次使用Fluent软件进行二次模拟。改造后的模拟结果显示:风流拐角处未见明显压力集中、风速变小现象,经计算每年可节省通风电费63.96万元,可达到较为理想的改造效果。

关键词：矿井通风直角弯局部阻力模拟改造

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具有界面复合活性层的高效纳滤膜构筑与性能

化学反应工程与工艺 2024年第2期40卷 116-125页

作者：邱杰孙哲建钱杰帖金鑫詹晓力张庆华浙江大学化学工程与生物工程学院杭州310058 浙江中烟工业有限责任公司杭州310008 浙江大学东海实验室浙江舟山316000

纳滤膜技术已广泛应用于水处理过程,但在长期运行过程中仍面临渗透通量下降和污染结垢等问题。本研究在多孔基材上将氨基功能化类沸石咪唑酯骨架-8(AZIF-8)与海藻酸钠(SA)水凝胶网络结合,构筑有机-无机纳米复合活性层高效凝胶网络,制... 详细信息

纳滤膜技术已广泛应用于水处理过程,但在长期运行过程中仍面临渗透通量下降和污染结垢等问题。本研究在多孔基材上将氨基功能化类沸石咪唑酯骨架-8(AZIF-8)与海藻酸钠(SA)水凝胶网络结合,构筑有机-无机纳米复合活性层高效凝胶网络,制备渗透性强、抗污染性能优异的复合纳滤膜(SAZM)。AZIF-8与SA水凝胶结合可以很好地克服纳米材料的团聚与相容性问题。杂化纳米凝胶网络赋予纳滤膜强的亲水性和抗污染性,为水分子的传输提供便捷路径。研究表明,SAZM对二价盐Na_(2)SO_(4)表现出稳定的截留性能,渗透通量从4.1×10^(-2)L/(m^(2)·h·k Pa)增加到16.3×10^(-2)L/(m^(2)·h·k Pa),提升297.6%。在牛血清白蛋白污染性实验中, SAZM表现出优异的抗污染性能,通量恢复率达95.1%。

关键词：纳滤膜纳米复合水凝胶抗污染脱盐

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胆维他治疗慢性肝病黄疸的临床研究

福州总医院学报 2001年第3期8卷 140-143页

作者：乐桥良张捷张志坚林克荣福州总医院消化内科

目的:评价胆维他(anetholtritione)治疗慢性肝病黄疸的效果。方法:将54例慢性肝病黄疸患者随机分为胆维他组和对照组;胆维他组在对照组基础(葡萄糖、肌苷、维生素C及肝泰乐等)上加用胆维他25mg～50mg/次,每日3次,疗程4周;测定治疗前后... 详细信息

目的:评价胆维他(anetholtritione)治疗慢性肝病黄疸的效果。方法:将54例慢性肝病黄疸患者随机分为胆维他组和对照组;胆维他组在对照组基础(葡萄糖、肌苷、维生素C及肝泰乐等)上加用胆维他25mg～50mg/次,每日3次,疗程4周;测定治疗前后总胆红素(TB)、直接胆红素(DB)、丙氨酸转氨酶(ALT)、门冬氨酸转氨酶(AST)、碱性磷酸酶(AKP)、白蛋白(ALB)及球蛋白(GLB)等含量的变化;并观察症状和体征变化及不良反应发生。结果:在治疗4周后,胆维他组和对照组临床显效率分别为28.57%(8/28)和11.54%(3/26),有效率分别为53.57%(15/28)和46.15%(12/26),无效率分别为17.86%(5/28)和42.31%(11/26),胆维他组临床总有效率82.14%(23/28)明显优于对照组57.69%(15/26)(P0.05);两组均无明显副作用。结论:胆维他能有效治疗慢性肝病的黄疸,且副作用少。

关键词：胆维他治疗慢性肝病黄疸对照组 ALB ALT AST 患者临床