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马铃薯仿生挖掘铲的设计与有限元静力学分析 被引量:17
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作者 赵萍 赵吉喆 +1 位作者 樊昱 田悦 《中国科技论文》 北大核心 2017年第22期2543-2548,共6页
针对马铃薯收获机常用挖掘铲达不到尽早漏土,易造成挖掘阻力大的问题,结合野猪拱嘴在外部形态和内在机能上独特的优势,以其为仿生对象,采用逆向工程技术设计了1种仿生挖掘铲。通过与常用铲的对比分析验证其性能,利用ANSYS软件对常用的... 针对马铃薯收获机常用挖掘铲达不到尽早漏土,易造成挖掘阻力大的问题,结合野猪拱嘴在外部形态和内在机能上独特的优势,以其为仿生对象,采用逆向工程技术设计了1种仿生挖掘铲。通过与常用铲的对比分析验证其性能,利用ANSYS软件对常用的三角平面铲、凹面铲及设计的仿生挖掘铲进行有限元静力学分析,得出相同条件下3种铲的应力及变形情况。结果表明,在相同条件下,仿生挖掘铲的应力及变形均为最小,且应力及变形与三角平面铲和凹面铲相比均减少60%左右,说明土壤对其作用力(阻力)最小,挖掘性能较好。仿生挖掘铲的设计为后续研究奠定了基础,也为块茎类收获机减阻技术提供了1种思路。 展开更多
关键词 农业机械 马铃薯收获机 挖掘铲 减阻 仿生学 有限元分析
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CeO_(2)含量、渗硼温度和时间对H13钢渗硼层组织和性能的影响 被引量:2
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作者 张炎威 郑权 +3 位作者 凡宇 梅顺齐 LYGDENOV Burial GURYEV Alexey 《机械工程材料》 CAS CSCD 北大核心 2021年第7期22-26,共5页
对H13钢表面进行渗硼处理,研究了稀土CeO_(2)含量(0,2%,4%,6%,质量分数)、渗硼温度(850,900,950,1000℃)及渗硼时间(2,3,4,5 h)对渗硼层组织和性能的影响。结果表明:随着渗硼温度的升高和时间的延长,渗硼层厚度先逐渐增大再趋于平缓;当C... 对H13钢表面进行渗硼处理,研究了稀土CeO_(2)含量(0,2%,4%,6%,质量分数)、渗硼温度(850,900,950,1000℃)及渗硼时间(2,3,4,5 h)对渗硼层组织和性能的影响。结果表明:随着渗硼温度的升高和时间的延长,渗硼层厚度先逐渐增大再趋于平缓;当CeO_(2)含量在0-2%时,硼原子的扩散激活能变化不大,从2%增大到4%时显著降低,且渗硼层厚度增加较快,从4%增大到6%时,扩散激活能基本不变,渗硼层厚度增加较慢;在渗硼温度为950℃,渗硼时间为4 h,CeO_(2)含量为4%条件下,渗硼层的孔洞最少,组织最致密,硬度最大,耐磨性最好。 展开更多
关键词 H13钢 CeO_(2)含量 渗硼温度 渗硼时间 硬度
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Ore-forming Fluid Systems and Mineralization in the Eastern Jiangnan Uplift in the Border Area of Anhui and Jiangxi Provinces, China 被引量:3
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作者 ZHOUTaofa YUANFeng +4 位作者 HOUMingjin fanyu DUJianguo ZHUGuang YUEShucang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第2期380-386,共7页
Obvious differences in mineralization characteristics exist between the southern and northern parts of the eastern part of the Jiangnan Uplift in northern Jiangxi Province and southern Anhui Province. The regional met... Obvious differences in mineralization characteristics exist between the southern and northern parts of the eastern part of the Jiangnan Uplift in northern Jiangxi Province and southern Anhui Province. The regional metallogeny is discussed, and the ore-forming fluid systems are classified in this article. It is proposed that the fluid ore-forming activities in the Jiangnan Uplift both in northern Jiangxi and southern Anhui have close relationships with the crust-mantle interaction and magmatic-tectonic activities. The types and scales of the mineralization on the both sides of the eastern Jiangnan Uplift were determined by fluid ore-forming systems and geological backgrounds. 展开更多
关键词 ore-forming fluid systems MINERALIZATION Jiangnan Uplift ANHUI northern Jiangxi
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PD-1/PD-L1在食管鳞状细胞癌中的表达及临床意义 被引量:14
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作者 李琦 李涛 +2 位作者 范羽 吕家华 袁道足 《肿瘤预防与治疗》 2018年第4期248-257,共10页
目的:探讨程序性死亡受体-1(programmed cell death-1,PD-1)及程序性死亡配体-1(programmed cell death-ligand 1,PD-L1)表达水平的高低与食管鳞癌的临床特征及疗效的相关性。方法:收集2012年1月至2013年12月期间四川省肿瘤医院收治的,... 目的:探讨程序性死亡受体-1(programmed cell death-1,PD-1)及程序性死亡配体-1(programmed cell death-ligand 1,PD-L1)表达水平的高低与食管鳞癌的临床特征及疗效的相关性。方法:收集2012年1月至2013年12月期间四川省肿瘤医院收治的,经内镜活检病理确诊的初治食管鳞癌患者87例,对患者的食管癌病理标本进行切片,行免疫组化染色检测PD-1和PD-L1的表达水平,并分析PD-1和PD-L1在食管鳞癌组织中的表达水平与食管鳞癌的临床特征及预后的关系。结果:全部样本中检出PD-L1的表达率为57.5%,其中大于cut-off值的高表达样本25例,即高表达率为28.7%,同时全部样本均未检出PD-1的表达;采用RECIST1.1指南对本研究的患者进行近期疗效评价所得的客观缓解率为58.6%;PD-L1的表达水平与客观缓解率呈负相关(P=0.049)。PD-L1在有远处转移的样本中高表达率显著高于无远处转移的样本(P=0.005)。多因素分析结果提示,PD-L1表达与食管鳞癌预后有相关性(P=0.043),是食管鳞癌的独立预后因素。结论:PD-L1在有远处转移的患者中表达高,PD-L1的高表达是影响食管鳞癌患者不良预后的潜在因素之一。 展开更多
关键词 食管肿瘤 PD-1 PD-L1 预后
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Effect of Quality Nursing Service on Depression and Anxiety of Elderly Inpatients
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作者 fanyu 《外文科技期刊数据库(文摘版)医药卫生》 2022年第10期067-070,共4页
Objective: to analyze the influence of quality nursing service on depression and anxiety of elderly inpatients. Methods: this study was divided into groups, mainly focusing on 116 elderly patients in chronic rehabilit... Objective: to analyze the influence of quality nursing service on depression and anxiety of elderly inpatients. Methods: this study was divided into groups, mainly focusing on 116 elderly patients in chronic rehabilitation department who were hospitalized in our hospital from June, 2020 to October, 2022. The observation group adopted high-quality nursing scheme and the control group adopted routine nursing scheme, and the nursing satisfaction of the two groups was compared. Depression and anxiety score;Nursing technology;Nursing environment and nursing knowledge. Results: comparing the observation group with the control group, it was found that the nursing satisfaction of the former was lower than that of the latter. Depression and anxiety scores were higher than those of the latter;Nursing technology, nursing environment and nursing knowledge are better than the latter. Conclusion: in the clinical nursing of elderly patients with chronic diseases treated by intravenous therapy, the provision of high-quality nursing services is beneficial to patients anxiety and depression, and has certain popularization and use significance. 展开更多
关键词 quality nursing elderly patients HOSPITALIZATION DEPRESSION anxious
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钢塑转换材料防腐质量的管控与提升
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作者 胡春英 丁雁祥 +1 位作者 范宇 徐凌枫 《城市燃气》 2021年第12期4-7,共4页
产品质量是安全的源头。为把控产品质量,城市燃气企业会针对各类工程材料组织供应商考察,此方式目前已形成行业惯例。钢塑转换材料因其安装位置的特殊性,尤其受到各城市燃气企业的关注。本文针对钢塑转换材料易出现的防腐质量不达标问... 产品质量是安全的源头。为把控产品质量,城市燃气企业会针对各类工程材料组织供应商考察,此方式目前已形成行业惯例。钢塑转换材料因其安装位置的特殊性,尤其受到各城市燃气企业的关注。本文针对钢塑转换材料易出现的防腐质量不达标问题通过对供应商的考察现场观察并着重分析钢塑转换材料厂家生产加工各工序的防腐质量风险点,提出相对应的管控举措,希望对钢塑转换材料生产厂家防腐质量的管控与提升提供一些思路,同时也可以作为城市燃气企业考察供应商工作的借鉴和参考。 展开更多
关键词 质量 安全 防腐 提升
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Thermal Conductivity Measurement of Semitransparent Media at Temperatures from 300 to 800 K by Hot-Wire Method 被引量:1
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作者 XinxinZhang fanyu 《Journal of Thermal Science》 SCIE EI CAS CSCD 1996年第1期11-15,共5页
In this paper,a new measurement technique for determining thermal conductivity of semitransparent media in the temperature range 300-800 K is reported.The experimental setup is based on the step power forced transient... In this paper,a new measurement technique for determining thermal conductivity of semitransparent media in the temperature range 300-800 K is reported.The experimental setup is based on the step power forced transient hot wire technique.It is assumed that the radiative contribution to the heat transfer process arises from emission,not from absorption.In this case,application of the'thermal quadruples'method allows a very simple construction of analytical models of the experimental setup.The parameter sensitivity analysis demonstrates that the thermal conductivity of semitransparent media can be determined from the hot wire temperature response. The experimental results of a kind of glass between 300 and 800 K are presented. 展开更多
关键词 thermal conductivity semitransparent medium hot wire method radiationconduction heat transfer.
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