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2019新型冠状病毒感染的肺炎79例临床特征及治疗分析 被引量:111
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作者 房晓伟 梅清 +9 位作者 杨田军 张蕾 杨云 王胤中 童飞 叶重阳 高宇 黄耀 耿士窠 潘爱军 《中国药理学通报》 CAS CSCD 北大核心 2020年第4期453-459,共7页
目的回顾性分析新型冠状病毒感染的肺炎(COVID-19)患者的临床特征,总结治疗经验,为抗疫一线临床医生提供诊疗参考。方法选取2020年1月22日至2月18日安徽省立医院感染病院收治的79例COVID-19患者为研究对象,其中普通型组55例,重型和危重... 目的回顾性分析新型冠状病毒感染的肺炎(COVID-19)患者的临床特征,总结治疗经验,为抗疫一线临床医生提供诊疗参考。方法选取2020年1月22日至2月18日安徽省立医院感染病院收治的79例COVID-19患者为研究对象,其中普通型组55例,重型和危重型组24例。收集并比较两组患者的临床资料,包括一般情况、临床症状、体征、实验室检查、肺部CT影像学及预后等,分析两组患者的治疗方案。结果 79例COVID-19患者平均年龄为45.1±16.6岁,其中男性45例。重型和危重型组较普通组患者的发病年龄更大,男性占比更多,合并更多的基础疾病,差异有统计学意义(P<0.05)。重型及危重型组较普通组患者的淋巴细胞(LYM)计数、白蛋白(ALB)降低更为明显;而中性粒细胞(NEU)百分比、C反应蛋白(CRP)、D二聚体、乳酸脱氢酶(LDH)、肌钙蛋白(cTnI)和尿素氮(BUN)的升高更加显著,差异有统计学意义(P <0. 05)。重型和危重型组患者接受抗病毒治疗的药物种类、糖皮质激素、丙种球蛋白及鼻导管吸氧应用比例显著多于普通型组,差异有统计学意义(P <0. 05)。截至2月18日,1例危重型患者因合并急性大面积脑梗最终死亡,34例康复出院,其余患者仍在接受治疗。结论既往伴有多种心脑血管疾病的老年患者更易发生重型及危重型COVID-19,且常常合并多个器官或系统的异常,临床医师应根据临床症状、体征及实验室检查结果及时做出判断并调整治疗方案。 展开更多
关键词 新型冠状病毒 新型冠状病毒肺炎 临床特征 洛匹那韦 干扰素 治疗 预后
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淫羊藿提取物对绝经后骨质疏松症大鼠PGE2及β2肾上腺素受体的影响 被引量:17
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作者 董重阳 师建平 +7 位作者 陈欣 谭峰 刘飞祥 李星 张明玥 柴毅 叶素敏 樊巧玲 《中华中医药杂志》 CAS CSCD 北大核心 2019年第5期2076-2079,共4页
目的:从预防骨丢失和促进骨再生两方面,研究中药淫羊藿提取物对绝经后骨质疏松症的防治作用。方法:通过去卵巢复制绝经后骨质疏松症模型;用淫羊藿提取物、强骨胶囊和己烯雌酚分别灌胃作用模型大鼠90d,观察比较各组骨密度(BMD g/cm3)、... 目的:从预防骨丢失和促进骨再生两方面,研究中药淫羊藿提取物对绝经后骨质疏松症的防治作用。方法:通过去卵巢复制绝经后骨质疏松症模型;用淫羊藿提取物、强骨胶囊和己烯雌酚分别灌胃作用模型大鼠90d,观察比较各组骨密度(BMD g/cm3)、骨小梁体积分数(BV/TV)、子宫重量/体质量(UW/BW),骨组织形态计量学指标、前列腺素E2(PGE2)和股骨β2肾上腺素能受体(ADRβ-2R)的表达。结果:与模型组比较,淫羊藿提取物能从骨组织形态学上有效防治绝经后骨质疏松症模型大鼠骨质疏松症,也能明显降低绝经后骨质疏松症模型大鼠血清PGE2水平(P<0.01)。同时,股骨头切片免疫组化分析显示:中、低剂量组淫羊藿提取物能显著降低ADRβ-2R的表达(P<0.05)。结论:淫羊藿提取物具有抑制骨吸收、促进骨形成的作用,其防治骨质疏松的作用机制涉及PGE2/ADRβ-2R信号通路。 展开更多
关键词 绝经后骨质疏松 淫羊藿 前列腺素E2 Β2肾上腺素受体
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蒙药蓝刺头调控FoxO/Wnt/β-catenin通路抗氧化应激防治绝经后骨质疏松研究 被引量:14
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作者 赵军 董重阳 +6 位作者 师建平 刘晋 党赢 常虹 海日 李婧 杨广源 《中华中医药杂志》 CAS CSCD 北大核心 2021年第1期116-121,共6页
目的:探讨蒙药蓝刺头抗氧化应激防治骨质疏松症(OP)作用;阐明蒙药蓝刺头调控FoxO/Wnt/β-catenin信号通路介导成骨细胞分化、骨形成机制。方法:77只SD雌性大鼠,随机分7组。制备绝经后骨质疏松症(PMOP)模型,阴道上皮角化实验验证造模成... 目的:探讨蒙药蓝刺头抗氧化应激防治骨质疏松症(OP)作用;阐明蒙药蓝刺头调控FoxO/Wnt/β-catenin信号通路介导成骨细胞分化、骨形成机制。方法:77只SD雌性大鼠,随机分7组。制备绝经后骨质疏松症(PMOP)模型,阴道上皮角化实验验证造模成功。造模后90d除模型组、假手术组予0.9%氯化钠溶液灌胃,其余各组予相应药物灌胃。采血离心血清;处死剔除双侧完整股骨并标记,右侧股骨4%多聚甲醛溶液固定,左侧股骨-196℃液氮贮存罐保存。右侧股骨采用骨密度仪测定离体骨骨密度(BMD)(股骨近端BMD)。ELISA法测定大鼠血清氧化应激指标。左侧股骨Western Blot法测骨p-p66(S36)、p66、β-catenin、Wnt2、FoxO3a蛋白。结果:蒙药蓝刺头可有效抑制FoxO转录,增强Wnt信号通路调控能力,促进骨成骨分化,使骨形成大于骨吸收;蒙药蓝刺头干预去卵巢PMOP模型大鼠,骨髓间充质干细胞抑制(BMSCs)向成骨方向分化,有效下调破骨细胞(OC)的形成。结论:蓝刺头能显著改善PMOP大鼠氧化应激状态;可交叉调控FoxO/Wnt/β-catenin通路,抑制氧化应激FoxO转录,上调Wnt表达,促进模鼠骨成骨分化、骨形成。 展开更多
关键词 绝经后骨质疏松症 蒙药 蓝刺头 补暖补精-清镇赫依-固骨质壮骨 氧化应激 FoxO/Wnt-β-catenin通路 分子机制
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Extracting more light for vertical emission:high power continuous wave operation of 1.3-μm quantum-dot photonic-crystal surface-emitting laser based on a flat band 被引量:9
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作者 Huan-Yu Lu Si-Cong Tian +6 位作者 Cun-Zhu Tong Li-Jie Wang Jia-Min Rong chong-yang Liu Hong Wang shi-Li Shu Li-Jun Wang 《Light(Science & Applications)》 SCIE EI CAS CSCD 2019年第1期167-172,共6页
For long distance optical interconnects,1.3-μm surface-emitting lasers are key devices.However,the low output power of several milliwatts limits their application.In this study,by introducing a two-dimensional photon... For long distance optical interconnects,1.3-μm surface-emitting lasers are key devices.However,the low output power of several milliwatts limits their application.In this study,by introducing a two-dimensional photonic-crystal and using InAs quantum dots as active materials,a continuous-wave,13.3-mW output power,1.3-μm wavelength,room-temperature surface-emitting laser is achieved.In addition,such a device can be operated at high temperatures of up to 90℃.The enhanced output power results from the flat band structure of the photonic crystal and an extra feedback mechanism.Surface emission is realized by photonic crystal diffraction and thus the distributed Bragg reflector is eliminated.The proposed device provides a means to overcome the limitations of low-power 1.3-μm surface-emitting lasers and increase the number of applications thereof. 展开更多
关键词 power crystal quantum
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钛合金铸造用型芯应用现状及展望 被引量:8
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作者 李重阳 刘鸿羽 +4 位作者 薛松海 刘时兵 史昆 张志勇 韩冬 《铸造》 CAS 北大核心 2021年第9期1023-1029,共7页
在成形具有复杂内腔结构的钛合金铸件时,型芯的正确选取和使用至关重要。就目前钛合金铸造应用最为广泛的三种型芯(石墨芯、金属芯、陶瓷芯)进行了系统阐述,并对未来型芯的发展进行了展望,以期为我国高端钛合金部件制造水平的提升提供... 在成形具有复杂内腔结构的钛合金铸件时,型芯的正确选取和使用至关重要。就目前钛合金铸造应用最为广泛的三种型芯(石墨芯、金属芯、陶瓷芯)进行了系统阐述,并对未来型芯的发展进行了展望,以期为我国高端钛合金部件制造水平的提升提供有益借鉴。 展开更多
关键词 钛合金铸造 石墨芯 金属芯 陶瓷芯 3D打印型芯
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导热橡胶研究进展 被引量:8
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作者 董梦杰 张继川 +6 位作者 刘力 范聪 袁重阳 王晓燕 侯冠一 温世鹏 王博伦 《高分子通报》 CAS CSCD 北大核心 2018年第4期15-26,共12页
橡胶是热的不良导体,但在实际应用中,许多领域需要橡胶具备一定的导热性能,以满足使用要求。因此,人们对于橡胶导热的研究越来越重视。本文概述了导热填料种类、形状、粒径、界面结合状态以及填料在橡胶基体中的分散性等因素对橡胶复合... 橡胶是热的不良导体,但在实际应用中,许多领域需要橡胶具备一定的导热性能,以满足使用要求。因此,人们对于橡胶导热的研究越来越重视。本文概述了导热填料种类、形状、粒径、界面结合状态以及填料在橡胶基体中的分散性等因素对橡胶复合材料导热性能的影响,从实验角度分析了填充型导热橡胶的导热机理,阐述了目前研究中人们所建立的各种物理和数学模型,浅析了这些模型的优缺点及适用范围,并将其应用于橡胶材料导热性能的预测,最后介绍了导热橡胶的应用领域,以及导热橡胶未来的发展方向。 展开更多
关键词 导热橡胶 导热机理 导热模型 导热性能
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压力敏感涂料内流场测量系统及涂料校准 被引量:7
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作者 郑立新 郝重阳 +3 位作者 刘波 陈柳生 史燚 朱柱国 《实验流体力学》 EI CAS CSCD 北大核心 2008年第3期86-88,93,共4页
压力敏感涂料(PSP)测量技术是上世纪80年代以来发展起来的全新的测量技术,具有测压范围广,对流场干扰小的突出特点。着眼于流体机械内部流场压力测量,依托国内现有条件,自主建立了压力敏感涂料测量系统,并对国产涂料进行了校准实验和处... 压力敏感涂料(PSP)测量技术是上世纪80年代以来发展起来的全新的测量技术,具有测压范围广,对流场干扰小的突出特点。着眼于流体机械内部流场压力测量,依托国内现有条件,自主建立了压力敏感涂料测量系统,并对国产涂料进行了校准实验和处理分析,检验了测量系统的有效性和可靠性,同时对国产涂料的特性与特点有了进一步的认识,为今后的工作打下了较好的基础。 展开更多
关键词 压力敏感涂料 压力测量 实验空气动力学 流体机械 校准实验
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大尺寸钛合金阀体石墨型铸造工艺研究
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作者 李重阳 刘时兵 +6 位作者 徐凯 李鸿举 李昕祺 岳野 刘天翼 倪嘉 shi Kun 《铸造》 CAS 北大核心 2023年第2期188-192,共5页
针对某大尺寸钛合金阀体铸件,对其结构进行分析后,设计了不同的浇注工艺,采用Pro-cast软件对该钛合金阀体铸件在不同浇注工艺下进行了石墨型铸造计算模拟。结果发现,不同的浇注系统会影响铸件内缺陷分布情况,且铸型预热温度的改变也会... 针对某大尺寸钛合金阀体铸件,对其结构进行分析后,设计了不同的浇注工艺,采用Pro-cast软件对该钛合金阀体铸件在不同浇注工艺下进行了石墨型铸造计算模拟。结果发现,不同的浇注系统会影响铸件内缺陷分布情况,且铸型预热温度的改变也会使铸件内缺陷体积发生变化。浇注工艺优化后,实际生产验证显示阀体铸件成形完整、无明显表面缺陷;X光检测结果显示铸件内部缺陷分布与模拟结果基本吻合。 展开更多
关键词 钛合金铸件 石墨型铸造 缺陷分布 铸造模拟
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Pregnancy Benefit of Acupuncture on in vitro Fertilization:A Systematic Review and Meta-Analysis
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作者 ZHANG Hao-ran ZHANG Cheng +8 位作者 MA Pei-hong SUN Cheng-yi SUN chong-yang LIU Xiao-yu PU Zhen-qing LIN Yu-han LIU Bao-yan LIU Cun-zhi YAN shi-yan 《Chinese Journal of Integrative Medicine》 SCIE CAS CSCD 2023年第11期1021-1032,共12页
Background:Currently,more and more infertility couples are opting for combined acupuncture to improve success rate of in vitro fertilization(IVF).However,evidence from acupuncture for improving IVF pregnancy outcomes ... Background:Currently,more and more infertility couples are opting for combined acupuncture to improve success rate of in vitro fertilization(IVF).However,evidence from acupuncture for improving IVF pregnancy outcomes remains a matter of debate.Objective:To quantitatively summarized the evidence of the efficacy of acupuncture among women undergoing IVF by means of systematic review and meta-analysis.Methods:Four English(PubMed,Web of Science,EMBASE,and Cochrane Register of Controlled Clinical Trials)and Four Chinese databases(Wanfang Databases,Chinese National Knowledge Infrastructure,Chinese Science and Technology Periodical Database,and SinoMed)were searched from database inception until July 2,2023.Randomized controlled trials(RCTs)that evaluated the acupuncture’s effects for women undergoing IVF were included.The subgroup analysis was conducted with respect to the age of participants,different acupuncture types,type of control,acupuncture timing,geographical origin of the study,whether or not repeated IVF failure,and acupuncture sessions.Sensitivity analyses were predefined to explore the robustness of results.The primary outcomes were clinical pregnancy rate(CPR)and live birth rate(LBR),and the secondary outcomes were ongoing pregnancy rate and miscarriage rate.Random effects model with I^(2)statistics were used to quantify heterogeneity.Publication bias was estimated by funnel plots and Egger’s tests.Results:A total of 58eligible RCTs representing 10,968 women undergoing IVF for pregnant success were identified.Pooled CPR and LBR showed a significant difference between acupuncture and control groups[69 comparisons,relative risk(RR)1.19,95%confidence intervals(CI)1.12 to 1.25,I^(2)=0],extremely low evidence;23 comparisons,RR 1.11,95%CI 1.02 to 1.21,I^(2)=14.6,low evidence,respectively.Only transcutaneous electrical acupoint stimulation showed a positive effect on both CPR(16 comparisons,RR 1.17,95%CI 1.06 to 1.29;I^(2)=0,moderate evidence)and LBR(9 comparisons,RR 1.20,95%CI 1.04 to 1.37;I^(2)=8.5,extremel 展开更多
关键词 ACUPUNCTURE ACUPUNCTURE STIMULATION
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Placebo response of sham acupuncture in patients with primary dysmenorrhea:A meta-analysis
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作者 chong-yang Sun Zhi-yi Xiong +7 位作者 Cheng-yi Sun Pei-hong Ma Xiao-yu Liu Chi-yun Sun Ze-yin Xin Bao-yan Liu Cun-zhi Liu shi-yan Yan 《Journal of Integrative Medicine》 SCIE CAS CSCD 2023年第5期455-463,共9页
Background The placebo response of sham acupuncture in patients with primary dysmenorrhea is a substantial factor associated with analgesia.However,the magnitude of the placebo response is unclear.Objective This meta-... Background The placebo response of sham acupuncture in patients with primary dysmenorrhea is a substantial factor associated with analgesia.However,the magnitude of the placebo response is unclear.Objective This meta-analysis assessed the effects of sham acupuncture in patients with primary dysmenorrhea and the factors contributing to these effects.Search strategy PubMed,Embase,Web of Science,and Cochrane CENTRAL databases were searched from inception up to August 20,2022.Inclusion criteria Randomized controlled trials(RCTs)using sham acupuncture as a control for female patients of reproductive age with primary dysmenorrhea were included.Data extraction and analysis Pain intensity,retrospective symptom scale,and health-related quality of life were outcome measures used in these trials.Placebo response was defined as the change in the outcome of interest from baseline to endpoint.We used standardized mean difference(SMD)to estimate the effect size of the placebo response.Results Thirteen RCTs were included.The pooled placebo response size for pain intensity was the largest(SMD=−0.99;95%confidence interval[CI],−1.31 to−0.68),followed by the retrospective symptom scale(Total frequency rating score:SMD=−0.20;95%CI,−0.80 to−0.39.Average severity score:SMD=−0.35;95%CI,−0.90 to−0.20)and physical component of SF-36(SMD=0.27;95%CI,−0.17 to 0.72).Studies using blunt-tip needles,single-center trials,studies with a low risk of bias,studies in which patients had a longer disease course,studies in which clinicians had<5 years of experience,and trials conducted outside Asia were more likely to have a lower placebo response.Conclusion Strong placebo response and some relative factors were found in patients with primary dysmenorrhea.PROSPERO registration number:CRD42022304215. 展开更多
关键词 Primary dysmenorrhea PAIN META-ANALYSIS Sham acupuncture Placebo response
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内蒙古罕山华北落叶松径向生长特征及水热环境响应
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作者 陈佳佳 周梅 +5 位作者 赵鹏武 许重阳 石亮 宝虎 刘艳军 曹光明 《林业科学研究》 CSCD 北大核心 2023年第4期50-58,共9页
[目的]以内蒙古罕山保护区为例,系统探讨我国北方半干旱区华北落叶松树干径向生长的变化规律及与环境因素(温度、降水等)的关系,为进一步认识半干旱区树木生长对气候变化的响应提供理论基础。[方法]在通辽市扎鲁特旗罕山国家级自然保护... [目的]以内蒙古罕山保护区为例,系统探讨我国北方半干旱区华北落叶松树干径向生长的变化规律及与环境因素(温度、降水等)的关系,为进一步认识半干旱区树木生长对气候变化的响应提供理论基础。[方法]在通辽市扎鲁特旗罕山国家级自然保护区,运用点触式树木径向生长测量仪对4株样树的径向生长开展了高分辨率的连续监测,并同步监测温度、降雨、土壤水分等环境因子,分析树木径向生长动态特征及影响因素。[结果]研究表明:华北落叶松径向生长具有白天收缩、夜间膨胀的日变化特征。在5—6月的树干收缩膨胀现象较7—9月更明显,且夜间膨胀量大于日间收缩量;在整个生长季尺度,华北落叶松的径向生长始终受到土壤温度的显著影响,但在不同生长阶段,土壤含水量是影响树干径向生长的重要因子。在极端丰水年(2021年)的生长季中的降雨高峰期之前(5月初—6月中),径向生长已达全年生长量的45%以上,说明土壤水分对径向生长的影响更直接,夏季降水量的直接影响较小,而冬季积雪在春季融化后的土壤水分供应则是决定径向生长的关键因子。[结论]在内蒙古半干旱地区,当年降水量对华北落叶松径向生长的直接贡献相对较小,主要是通过转化成土壤水的形式间接影响树木生长;土壤温度和土壤水分是影响径向生长的重要因子,在土壤水分未得到降雨有效补充的生长季初期,树木径向生长主要依靠土壤水的前期存量。 展开更多
关键词 中国北方半干旱区 华北落叶松人工林 树木径向生长 水热环境因子变化
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Placebo Response among Different Types of Sham Acupuncture for Low Back Pain:A Systematic Review and Meta-Analysis of Randomized Controlled Trials
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作者 XIONG Zhi-yi LIU Xiao-yu +6 位作者 MA Pei-hong SUN chong-yang SUN Cheng-yi LIU Ting-lan LIU Bao-yan LIU Cun-zhi YAN shi-yan 《Chinese Journal of Integrative Medicine》 SCIE CAS CSCD 2023年第10期941-950,共10页
Background: Low back pain(LBP) is a prevalent and debilitating condition that poses a significant burden on healthcare systems. Acupuncture has been proposed as a promising intervention for LBP, but the evidence suppo... Background: Low back pain(LBP) is a prevalent and debilitating condition that poses a significant burden on healthcare systems. Acupuncture has been proposed as a promising intervention for LBP, but the evidence supporting its specific effect is insufficient, and the use of sham acupuncture as a control in clinical trials presents challenges due to variations in sham acupuncture techniques and the magnitude of the placebo effect.Objective: To investigate the magnitude of the placebo response of sham acupuncture in trials of acupuncture for nonspecific LBP, and to assess whether different types of sham acupuncture are associated with different responses. Methods: Four databases including PubMed, EMBASE, MEDLINE, and the Cochrane Library were searched through April 15, 2023, and randomized controlled trials(RCTs) were included if they randomized patients with LBP to receive acupuncture or sham acupuncture intervention. The main outcomes included the placebo response in pain intensity, back-specific function and quality of life. Placebo response was defined as the change in these outcome measures from baseline to the end of treatment. Random-effects models were used to synthesize the results, standardized mean differences(SMDs, Hedges’ g) were applied to estimate the effect size. Results: A total of 18 RCTs with 3,321 patients were included. Sham acupuncture showed a noteworthy pooled placebo response in pain intensity in patients with LBP [SMD –1.43, 95% confidence interval(CI) –1.95 to –0.91, I2=89%]. A significant placebo response was also shown in back-specific functional status(SMD –0.49, 95% CI –0.70 to –0.29, I2=73%),but not in quality of life(SMD 0.34, 95% CI –0.20 to 0.88, I2=84%). Trials in which the sham acupuncture penetrated the skin or performed with regular needles had a significantly higher placebo response in pain intensity reduction, but other factors such as the location of sham acupuncture did not have a significant impact on the placebo response.Conclusions: Sham acupuncture is a 展开更多
关键词 low back pain sham acupuncture placebo response META-ANALYSIS randomized controlled trial
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钛合金铸造用支撑座砂芯改性工艺研究
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作者 李重阳 白志宇 +4 位作者 刘时兵 韩鹏江 刁云峰 李鸿举 李昕祺 《铸造》 CAS 北大核心 2023年第8期980-985,共6页
简要分析了某支撑座型芯常规材质制备的局限性,提出了一种基于3D打印砂芯的钛合金铸造用砂芯改性工艺。通过两次无机粘结剂的浸渗、焙烧处理,使砂芯在具备一定强度的同时维持高的尺寸精度,并且具有十分优异的脱芯能力。在实际生产验证中... 简要分析了某支撑座型芯常规材质制备的局限性,提出了一种基于3D打印砂芯的钛合金铸造用砂芯改性工艺。通过两次无机粘结剂的浸渗、焙烧处理,使砂芯在具备一定强度的同时维持高的尺寸精度,并且具有十分优异的脱芯能力。在实际生产验证中,铸件表面质量高,荧光检测无明显线性缺陷,铸件表面污染层厚度小于20μm。 展开更多
关键词 钛合金 支撑座型芯 3D打印砂芯 无机粘结剂
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热处理工艺对铸造/激光增材制造复合制备Ti-6Al-4V合金组织和性能的影响 被引量:4
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作者 薛松海 李重阳 +4 位作者 李雪辰 刘鸿羽 刘时兵 曲玉福 刘田雨 《铸造》 CAS 北大核心 2021年第7期800-805,共6页
研究了热处理工艺对复合制备Ti-6Al-4V合金组织和性能的影响。结果表明,制备的Ti-6Al-4V试样有3个典型区域,分别为激光增材制造区、铸造基底区和铸造/激光增材制造冶金结合区;激光增材制造区由网篮组织构成,铸造基底区由魏氏组织构成,... 研究了热处理工艺对复合制备Ti-6Al-4V合金组织和性能的影响。结果表明,制备的Ti-6Al-4V试样有3个典型区域,分别为激光增材制造区、铸造基底区和铸造/激光增材制造冶金结合区;激光增材制造区由网篮组织构成,铸造基底区由魏氏组织构成,而铸造/激光增材制造结合区微观组织取决于热处理工艺;铸态和固溶态呈魏氏组织,而固溶时效和热等静压+固溶时效态呈网篮组织。固溶时效态由于组织均匀性较高、析出次生α相,从而使得合金不但具有较高的强度(915 MPa),而且具有较高的伸长率(11%)。 展开更多
关键词 铸造/激光增材制造复合制造 TI-6AL-4V 热处理工艺 微观组织 力学性能
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Recent advances in catalytica symmetric Buchner reaction
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作者 chong-yang shi Guang-Yu Zhu +2 位作者 Yin Xu Ming-Yu Teng Long-Wu Ye 《Chinese Chemical Letters》 SCIE CAS CSCD 2023年第12期87-92,共6页
Bichner reaction,as a unique type of expansive dearomatization,has become a practical strategy for the straightforward assembly of valuable functionalized cycloheptatrienes from ubiquitous aromatic precursors.Although... Bichner reaction,as a unique type of expansive dearomatization,has become a practical strategy for the straightforward assembly of valuable functionalized cycloheptatrienes from ubiquitous aromatic precursors.Although the asymmetric version has been investigated since the early 1990s,enantioselective Bichner reaction is still limited by the catalyst type and substrate scope.This review aims to propose the limitation and possible development direction of this field by summarizing the evolution of catalytic asymmetric Bichner reaction,which is organized on the basis of intra-and intermolecular reactions.Considering the different metal carbene precursors,the reactions are further classified by carbene sources. 展开更多
关键词 Bichner reaction Diazo compounds Metal carbenes Cycloheptatrienes Dearomatization reactions
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Elusive workers are more likely to differentiate into replacement reproductives than aggressive workers in a lower termite
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作者 Zhuang-Dong Bai chong-yang shi +1 位作者 David Sillam-Dusses Rui-Wu Wang 《Current Zoology》 SCIE CAS CSCD 2023年第3期332-338,共7页
One of the most intriguing questions in eusocial insects is to understand how the overt reproductive conflict in the colony appears limited when queens or kings are senescent or lost because the morphologically simila... One of the most intriguing questions in eusocial insects is to understand how the overt reproductive conflict in the colony appears limited when queens or kings are senescent or lost because the morphologically similar individuals in the colony are reproductively totipotent.Whether there are some individuals who preferentially differentiate into replacement reproductives or not has received little attention.The consistent individual behavioral differences(also termed“animal personality”)of individuals from the colony can shape cunningly their task and consequently affect the colony fitness but have been rarely investigated in eusocial insects.Here,we used the termite Reticulitermes labralis to investigate if variations in individual personalities(elusiveness and aggressiveness)may predict which individuals will perform reproductive differentiation within colonies.We observed that when we separately reared elusive and aggressive workers,elusive workers differentiate into reproductives significantly earlier than aggressive workers.When we reared them together in the proportions 12:3,10:5,and 8:7(aggressive workers:elusive workers),the first reproductives mostly differentiated from the elusive workers,and the reproductives differentiated from the elusive workers significantly earlier than from aggressive workers.Furthermore,we found that the number of workers participating in reproductive differentiation was significantly lower in the groups of both types of workers than in groups containing only elusive workers.Our results demonstrate that the elusiveness trait was a strong predictor of workers’differentiation into replacement reproductives in R.labralis.Moreover,our results suggest that individual personalities within the insect society could play a key role in resolving the overt reproductive conflict. 展开更多
关键词 consistent individual behavioral differences reproductive conflict reproductive differentiation Reticulitermes labralis TERMITE
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含镁三元系锰电解液理化性能研究 被引量:3
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作者 李重洋 钱振 +2 位作者 时启龙 何利民 熊雪良 《矿冶工程》 CAS CSCD 北大核心 2019年第4期79-82,88,共5页
研究了MgSO4-MnSO4-(NH4)2SO4三元系锰电解液的理化性能。选取电解锰合格液作为研究对象,研究了温度、溶液成分对锰电解液密度、电导率和缓冲能力的影响。结果表明,锰电解液密度随溶液温度降低、硫酸铵浓度和镁离子浓度升高而增加;镁离... 研究了MgSO4-MnSO4-(NH4)2SO4三元系锰电解液的理化性能。选取电解锰合格液作为研究对象,研究了温度、溶液成分对锰电解液密度、电导率和缓冲能力的影响。结果表明,锰电解液密度随溶液温度降低、硫酸铵浓度和镁离子浓度升高而增加;镁离子对电解液密度影响较大,镁离子浓度从0增至30 g/L,40℃下锰电解液密度从1.133 g/mL增至1.263 g/mL。电导率随溶液温度、硫酸铵浓度升高而增加,随镁离子浓度升高而降低;硫酸铵浓度从70 g/L增至100 g/L时,溶液电导率增幅超过27%;镁离子浓度从0增至30 g/L时,溶液电导率降幅将近14%。硫酸铵能显著增加锰电解液的缓冲能力,镁离子浓度对缓冲容量影响不大,但是镁离子浓度超过25 g/L后会降低锰电解液对pH值的调节能力。 展开更多
关键词 电解锰 含镁三元系 溶液电导率 溶液密度 镁离子
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不同浓度余氯对4种沉水植物生长影响的比较研究 被引量:2
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作者 黄伟平 李豪 +3 位作者 田方鑫 赵重阳 刘世婷 陈洪斌 《四川环境》 2022年第2期37-43,共7页
为筛选出具有耐氯性的沉水植物,选取金鱼藻(Ceratophyllum demersum)、苦草(Vallisneria natans)、水蕴草(Elodea densa)、轮叶黑藻(Hydrilla verticillata)4种沉水植物为研究对象,在静态模拟条件下设置0、0.4、0.8、1.2mg/L的梯度浓度... 为筛选出具有耐氯性的沉水植物,选取金鱼藻(Ceratophyllum demersum)、苦草(Vallisneria natans)、水蕴草(Elodea densa)、轮叶黑藻(Hydrilla verticillata)4种沉水植物为研究对象,在静态模拟条件下设置0、0.4、0.8、1.2mg/L的梯度浓度余氯,通过表观生长目测估计方法和测定叶绿素含量的变化,比较研究不同浓度余氯对沉水植物的生长影响。结果表明,4种沉水植物中水蕴草的表观生长状况最好,叶绿素含量最高,能在0.8 mg/L的余氯浓度下存活和生长,表现出较好的耐氯性。对于以含氯尾水作为补水的湿地公园,本文研究结果可为其沉水植物的选择提供参考,以提高尾水回用的生态效益。 展开更多
关键词 尾水回用 耐氯性 沉水植物
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‘临稻16’和‘临稻10’光合速率以及蔗糖、淀粉积累的比较研究 被引量:2
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作者 冯尚宗 李重阳 +5 位作者 王新娟 王世伟 娄华敏 周伟 刘宁 杨兴洪 《植物生理学报》 CAS CSCD 北大核心 2019年第3期359-366,共8页
本文以‘临稻16’和‘临稻10’作为实验材料,探讨‘临稻16’相对于‘临稻10’产量高的生理基础。研究结果表明:‘临稻16’在开花前以及灌浆中期的剑叶净光合速率较‘临稻10’高,为‘临稻16’后期籽粒灌浆和淀粉积累提供了物质基础。蔗... 本文以‘临稻16’和‘临稻10’作为实验材料,探讨‘临稻16’相对于‘临稻10’产量高的生理基础。研究结果表明:‘临稻16’在开花前以及灌浆中期的剑叶净光合速率较‘临稻10’高,为‘临稻16’后期籽粒灌浆和淀粉积累提供了物质基础。蔗糖合成和淀粉代谢的关键酶活性测定结果表明,‘临稻16’在开花前、灌浆中期以及灌浆期剑叶蔗糖合成酶(SS)和蔗糖磷酸合成酶(SPS)活性均显著高于‘临稻10’,籽粒中腺苷二磷酸葡萄糖焦磷酸化酶(AGPase)活性在‘临稻16’中也表现出较高的活性,‘临稻16’籽粒中淀粉的含量在灌浆后期显著高于‘临稻10’。灌浆后期‘临稻16’仍然保持较高的蔗糖和淀粉代谢相关酶活性,淀粉合成速率较快,有利于‘临稻16’籽粒中淀粉的积累。而‘临稻10’淀粉合成速率明显减缓。这说明决定‘临稻16’产量和出米率的主要因素集中在灌浆中期,为‘临稻16’高产奠定基础。 展开更多
关键词 临稻 光合速率 蔗糖代谢 淀粉积累
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Effectiveness of sharp recanalization of superior vena cava-right atrium junction occlusion 被引量:2
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作者 Xiao-Wen Wu Xu-Ya Zhao +8 位作者 Xing Li Jun-Xiang Li Zong-yang Liu Zhi Huang Ling Zhang chong-yang Sima Yu Huang Lei Chen shi Zhou 《World Journal of Clinical Cases》 SCIE 2021年第16期3848-3857,共10页
BACKGROUND Conventional recanalization techniques may fail in patients with completely occluded superior vena cava(SVC).AIM To analyze the effectiveness and complications of sharp recanalization for completely occlude... BACKGROUND Conventional recanalization techniques may fail in patients with completely occluded superior vena cava(SVC).AIM To analyze the effectiveness and complications of sharp recanalization for completely occluded SVC.METHODS This was a retrospective study of patients that underwent puncture and recanalization of the SVC between January 2016 and December 2017 at our hospital.Sharp recanalization was performed using the RUPS-100 system.The patients were followed for 12 mo.The main outcomes were the patency rate of SVC and arteriovenous fistula flow during dialysis.RESULTS The procedure was successful in all 14 patients(100%).Blood pressure in the distal SVC decreased in all 14 cases(100%)from 26.4±2.7 cmH2O to 14.7±1.3 cmH2O(P<0.05).The first patency rates of the SVC at 24 h and at 3,6,9 and 12 mo after sharp recanalization were 100%,92.9%,85.7%,78.6%and 71.4%,respectively.There were two(14.3%)severe,one(7.1%)moderate and one(7.1%)minor complication.The severe complications included one case of pericardial tamponade and one case of hemothorax.CONCLUSION The results suggest that sharp recanalization can be an additional tool to extend or renew the use of an occluded upper extremity access for hemodialysis.This could be of use in patients with long-term maintenance hemodialysis in whom the maintenance of central venous access is often a challenge. 展开更多
关键词 HEMODIALYSIS Superior vena cava occlusion Vascular patency Arteriovenous fistula Arteriovenous graft
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