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LIQUIDUS OF Ag-Cu-Bi SYSTEM
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作者 LIU Shuqi SUN Wenqing Deptrtment of Chemistry,Peking University,Beijing,China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1989年第8期151-152,共2页
The diagram of Ag-Cu-Bi system was constructed from the investigation of 12 internal sec- tions by DTA heating as well as cooling curves in an atmosphere of dry N_2.The composi- tion of ternary eutectic point melting ... The diagram of Ag-Cu-Bi system was constructed from the investigation of 12 internal sec- tions by DTA heating as well as cooling curves in an atmosphere of dry N_2.The composi- tion of ternary eutectic point melting at 258℃ lies in Ag(5.0)-Cu(0.5)-Bi(94.5) at.-%.The liquiduses of Ag-Cu,Ag-Bi and Cu-Bi binaries were reinvestigated. 展开更多
关键词 Ag-Cu-bi ternary system LIQUIDUS
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Bi/nZVI在柠檬酸缓冲溶液中电催化降解磺胺二甲基嘧啶
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作者 唐紫依 刘杰 龚建宇 《环境化学》 北大核心 2026年第1期436-444,共9页
随着医药和畜牧业的快速发展,大量磺胺类药物残余物进入水体,引起一系列环境和健康问题.改性纳米零价铁(nZVI)通过激活分子氧产H_(2)O_(2),发生类芬顿反应快速高效降解SAs,引起广泛关注.本文利用铋改性纳米零价铁(Bi/nZVI)在柠檬酸(CA)... 随着医药和畜牧业的快速发展,大量磺胺类药物残余物进入水体,引起一系列环境和健康问题.改性纳米零价铁(nZVI)通过激活分子氧产H_(2)O_(2),发生类芬顿反应快速高效降解SAs,引起广泛关注.本文利用铋改性纳米零价铁(Bi/nZVI)在柠檬酸(CA)-柠檬酸钠(NaCA)缓冲溶液中电催化氧化降解磺胺二甲基嘧啶(SMZ).结果表明,Bi的掺杂有利于降低分子氧活化生成H_(2)O_(2)的反应活化能,柠檬酸根与铁络合生成的柠檬酸亚铁络合物与体系自发生成的H_(2)O_(2)发生类芬顿反应,Fe^(2+)/Fe^(3+)氧化还原电位降低,利于铁循环过程,从而强化对SMZ的降解效果.在该体系中存在·OH、·O_(2)^(-)、^(1)O_(2)等3种活性氧物种(ROS),其贡献大小依次为:·OH>·O_(2)^(-)>^(1)O_(2).质谱分析推测,在该体系下,SMZ可能的降解路径主要包括4方面:羟基化加成、磺酰胺基SO_(2)脱除、S—N键断裂和含氮杂环C—N/C=N键断裂.这种新型体系的构建不仅为水体中磺胺类药物的去除提供了新的技术方法,也为其他有机污染物的处理提供了一定的理论支撑. 展开更多
关键词 电催化 bi/nZVI 柠檬酸缓冲液 磺胺二甲基嘧啶 络合
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Sn-Bi基焊料界面可靠性关键问题与改性策略研究进展
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作者 赏敏 马海涛 +2 位作者 马浩然 王加俊 王云鹏 《表面技术》 北大核心 2026年第3期219-243,共25页
系统综述了旨在提升Sn-Bi焊点界面可靠性的多层次改性策略。首先,评述了通过焊料合金化调控其本征性能的方法,系统分析了添加Ag、Cu、Ni、In、Sb、Zn、Co等元素对焊料微观结构、力学性能及界面反应动力学的影响。其次,探讨了以石墨烯为... 系统综述了旨在提升Sn-Bi焊点界面可靠性的多层次改性策略。首先,评述了通过焊料合金化调控其本征性能的方法,系统分析了添加Ag、Cu、Ni、In、Sb、Zn、Co等元素对焊料微观结构、力学性能及界面反应动力学的影响。其次,探讨了以石墨烯为代表的纳米颗粒强化机制,阐明其在细化晶粒和抑制IMC生长方面的作用。随后,重点阐述了以基板改性为核心的界面工程策略,深入剖析了Ni基金属镀层和Ni-P、Ni-W-P等先进复合镀层作为扩散阻挡层的核心机理,即通过改变界面反应热力学路径来抑制原子互扩散。同时,也关注了复合改性方法,如焊料合金化与基板表面处理,如ENEPIG的协同作用。最后,对未来研究方向进行了展望,指出开发高熵/非晶合金等新型阻挡层,并结合计算材料学与先进原位表征技术,将是实现下一代高可靠性Sn-Bi焊点界面“按需设计”的关键。 展开更多
关键词 Sn-bi焊料 界面可靠性 金属间化合物 bi相偏析 合金化 扩散阻挡层 纳米增强
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Bi基催化剂CO_(2)还原反应生成甲酸的研究进展
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作者 宫智超 莫瑞 +2 位作者 辛雯 王文飞 聂春红 《化工科技》 2026年第1期59-64,共6页
可持续地将CO_(2)转化为高附加值的化学品和燃料是解决CO_(2)过量排放问题、缓解化石燃料短缺、维持自然界碳循环平衡的一种有希望的解决方案。催化体系的开发对提高电催化CO_(2)转化的效率和选择性具有重要意义。甲酸(HCOOH)是CO_(2)... 可持续地将CO_(2)转化为高附加值的化学品和燃料是解决CO_(2)过量排放问题、缓解化石燃料短缺、维持自然界碳循环平衡的一种有希望的解决方案。催化体系的开发对提高电催化CO_(2)转化的效率和选择性具有重要意义。甲酸(HCOOH)是CO_(2)电催化还原的重要产物之一,其化工和能源领域具有广泛的应用价值。Bi基材料因其低成本、环境友好等优势,在该领域展现出良好的催化潜力,但仍需克服诸多挑战。综述了常温常压水相体系中Bi基材料电催化CO_(2)还原制甲酸研究进展,从Bi金属、Bi单原子、Bi合金及Bi复合材料系统分析了各类催化剂的特性与优势,并对Bi基催化剂的未来发展方向进行了展望。 展开更多
关键词 电催化 CO_(2)还原 bi基催化剂 甲酸 电化学
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Dynamic Evolution of the Eclipsing Overcontact Binary Star System BI CVn
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作者 İ.Bulut M.Güneş Ç.Nehir 《Research in Astronomy and Astrophysics》 2025年第8期16-28,共13页
We present a comprehensive analysis of BI CVn,an eclipsing overcontact binary system.New BVR photometric observations,combined with available spectroscopic data,were analyzed simultaneously using the Wilson–Devinney ... We present a comprehensive analysis of BI CVn,an eclipsing overcontact binary system.New BVR photometric observations,combined with available spectroscopic data,were analyzed simultaneously using the Wilson–Devinney method to derive the orbital and physical parameters of the system.The resulting stellar parameters are M1=0.58±0.01M⊙,M2=1.42±0.02M⊙,R1=0.88±0.01R⊙,R2=1.31±0.01R⊙,with an orbital separation of a=2.80±0.01R⊙.Based on all available CCD times of minimum light,including both ground-based and T ESS observations,the(O-C)diagram of BI CVn was analyzed.T he orbital period exhibits a long-term decrease at a rate of-2.3239(±0.0001)×10-8 day yr-1,likely due to mass transfer from the more massive to the less massive component.Superimposed on this trend is a cyclic variation with a period of 56.84±0.08 yr,indicative of a light-travel time effect caused by a third body,whose estimated mass is 0.63±0.02M⊙.Using these derived parameters,we modeled the binary’s evolution through non-conservative processes with the Binary Star Evolution code.The evolutionary tracks of the components were examined in multiple parameter planes,leading to an estimated merger timescale of approximately 2.70 Gyr. 展开更多
关键词 (stars:)binaries:eclipsing stars:fundamental parameters stars:individual(bi CVn)
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Atomic-scale characterization of epitaxial Bi(110)/VTe_(2)bilayer heterostructure
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作者 WANG Qiwei LI Shaochun 《物理学进展》 北大核心 2026年第1期13-21,共9页
Interplay between topology and magnetism can give rise to exotic properties in topological materials.Two-dimensional bismuth has been extensively studied owing to its topological states with a strong spin-orbit coupli... Interplay between topology and magnetism can give rise to exotic properties in topological materials.Two-dimensional bismuth has been extensively studied owing to its topological states with a strong spin-orbit coupling,and 1T-VTe_(2)monolayer theoretically predicted to host an intrinsic magnetism as experimentally suggested.In this work,we successfully constructed a vertical heterostructure composed of the two-dimensional Bi(110)monolayer and 1T-VTe_(2)monolayer by using molecular beam epitaxy(MBE).Scanning tunneling microscopy(STM)measurements revealed that the growth of Bi preferably occurs along the step edges of the VTe_(2)monolayer,forming a Bi(110)monolayer on top of the VTe_(2)monolayer next to a peripheral Bi bilayer.The Bi(100)/VTe_(2)heterostructure exhibits a specific lattice registry with a well-defined moiréperiodicity.Scanning tunneling spectroscopy(STS)measurements further unveiled an universal suppression in the local density-of-states at the boundary of the Bi(110)/VTe_(2)bilayer.By examining the atomic structures of Bi(110)boundaries,we found this effect does not originate from the previously proposed atomic reconstruction at the step edge of Bi(110),but is likely related to the magnetic properties of the VTe_(2)monolayer. 展开更多
关键词 bi/VTe_(2)heterostructure moirépattern edge state molecular beam epitaxy scanning tunneling microscopy
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395BI大臂天轮耳座变形矫正工艺的创新与应用
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作者 王宇宁 张永强 《机电信息》 2026年第2期79-82,共4页
围绕395BI电铲大臂天轮耳座变形问题展开研究,详细剖析了耳座变形的原因,介绍了具有创新性的矫正补孔维修方案,阐述了实施过程中的工艺技术难点及解决措施,包括切割、矫正、焊接等具体工艺步骤和参数。通过该创新维修工艺,有效解决了设... 围绕395BI电铲大臂天轮耳座变形问题展开研究,详细剖析了耳座变形的原因,介绍了具有创新性的矫正补孔维修方案,阐述了实施过程中的工艺技术难点及解决措施,包括切割、矫正、焊接等具体工艺步骤和参数。通过该创新维修工艺,有效解决了设备故障,降低了检修成本,提高了设备出动率,为同类设备的维修提供了可借鉴的宝贵经验。 展开更多
关键词 395bi 大臂天轮 耳座变形 矫正工艺
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神经内镜微创手术与传统开颅手术对脑出血患者NIHSS评分及BI评分影响的对比研究
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作者 史霄汉 李辉 魏震 《四川生理科学杂志》 2026年第3期659-661,664,共4页
目的:探讨传统开颅手术与神经内镜微创手术对脑出血患者美国国立卫生研究院卒中量表评分(National Institute of Health Stroke Scale Score,NIHSS)及巴塞尔指数评分(Barthel Index Score,BI)的影响。方法:回顾性收集2022年1月至2023年... 目的:探讨传统开颅手术与神经内镜微创手术对脑出血患者美国国立卫生研究院卒中量表评分(National Institute of Health Stroke Scale Score,NIHSS)及巴塞尔指数评分(Barthel Index Score,BI)的影响。方法:回顾性收集2022年1月至2023年1月期间本院收治的200例脑出血患者的临床资料。根据治疗方式不同将患者分为对照组(实施传统开颅手术,150例)和观察组(实施神经内镜微创手术,50例)。收集并比较两组术后神经功能恢复情况、术后日常生活活动能力、手术相关指标、术后并发症发生情况。结果:随着术后时间增长,两组NIHSS评分均降低;术后2、3、6、12 m,观察组NIHSS评分均低于对照组(P<0.05)。随着术后时间增长,两组BI评分均提高;术后2、3、6、12 m,观察组BI评分均高于对照组(P<0.05)。观察组手术时间、术后住院时间均短于对照组,术中出血量少于对照组(P<0.05)。观察组术后并发症发生率低于对照组(P<0.05)。结论:与传统开颅手术比较,神经内镜微创手术更有利于促进脑出血患者神经功能恢复、提升日常生活活动能力,且兼具操作时间短、出血量少、住院时间短、并发症发生率低等优势,预后情况良好,值得临床推广应用。 展开更多
关键词 传统开颅手术 神经内镜微创手术 脑出血 NIHSS评分 bi评分
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Juan Bi Tong Luo,a traditional Chinese medicine,ameliorates diabetic peripheral neuropathy by downregulating the MAPK/NF-κB signaling pathway
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作者 Wei Liu Yue Zhu +1 位作者 Wei Song Fei Huang 《Traditional Medicine Research》 2026年第3期56-64,共9页
Background:Inflammation,caused by prolonged hyperglycemia,plays a substantially more important part in the progression of diabetic peripheral neuropathy(DPN).Notably,the MAPK pathway that mediates the Nuclear Factor-k... Background:Inflammation,caused by prolonged hyperglycemia,plays a substantially more important part in the progression of diabetic peripheral neuropathy(DPN).Notably,the MAPK pathway that mediates the Nuclear Factor-kappa B(NF-κB)pathway contributes to inflammation-induced peripheral nerve damage,affecting cell survival.Juan Bi Tong Luo(JBTL),a traditional Chinese medicine(TCM),has demonstrated favorable results in alleviating pain and numbness in patients with DPN;however,whether JBTL exerts its effect through the MAPK mediating NF-κB pathway remains unclear.Methods:This study investigated whether JBTL modulates apoptosis in DPN models and Schwann cells cultured in 100 mM of glucose by MAPK/NF-κB.Results:The JBTL altered inflammation,reduced peripheral nerve tissue damage,and improved cell survival rates by down-regulating MAPK/NF-κB.Conclusion:Our findings demonstrate that the effect of JBTL on DPN is likely mediated by suppressing inflammation induced by the MAPK/NF-κB pathway,thus providing evidence for the clinical efficacy of JBTL in treating DPN. 展开更多
关键词 Juan bi Tong Luo diabetic peripheral neuropathy INFLAMMATION
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Effect of drought and elevated temperature on the physiological and biochemical properties of C_(3)and C_(4)halophytes in Amaranthaceae
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作者 Zulfira RAKHMANKULOVA Elena SHUYSKAYA +3 位作者 Maria PROKOFIEVA Kristina TODERICH Luizat SAIDOVA ZHANG Yuanming 《Journal of Arid Land》 2026年第1期131-149,共19页
Rising temperatures and increased droughts caused by climate change significantly reduce crop yields.Halophytes with different photosynthetic metabolism types have specific mechanisms for resistance to climatic factor... Rising temperatures and increased droughts caused by climate change significantly reduce crop yields.Halophytes with different photosynthetic metabolism types have specific mechanisms for resistance to climatic factors.This study analyzed the morphophysiological,biochemical,and molecular-genetic mechanisms of tolerance and adaptation in halophytes,promising candidates for the restoration of salt affected lands in arid and semi-arid areas.Experiments under drought(D)and elevated temperature(eT),as well as their combined action(eT+D),were performed on Atriplex verrucifera M.Bied.(C_(3)plant)and Climacoptera crassa(M.Bieb.)Botsch.(C_(4)-NAD-ME plant)with different types of photosynthesis.The activity of photosystem I(PSI)and the efficiency of photosystem II(PSII)were measured,along with the expression of genes involved in the light(psaA,psaB,psbA,CAB,Fd1,PGR5,and ndhH)and dark(rbcL,Ppc2,and PPDK)reactions of photosynthesis.The content of key carboxylating enzymes ribulose-1,5-bisphosphate carboxylase/oxygenase(Rubisco)and phosphoenolpyruvate carboxylase(PEPC),as well as the photorespiration enzyme glycine decarboxylase(GDC),were assessed.Plant growth and water-salt balance parameters,and activity of enzymes in the malate dehydrogenase(MDH)system nicotinamide adenine dinucleotide(phosphate)(NAD(P))-MDH and NAD(P)-malic enzyme(ME)were also examined.A multivariate analysis of the experimental results revealed that A.verrucifera and C.crassa were both resistant to the effects of these climatic stressors.The tolerance mechanisms of both species were significantly influenced by a high level of photosynthetic plasticity.Nevertheless,differences were observed in the protective mechanisms underlying tolerance.In the C_(3)species,dissipative processes associated with non-photochemical quenching(NPQ)of PSII and MDH system enzymes(malate valves)were activated,particularly under osmotic stress.The negative effects in the C_(3)plants were caused by the combined action of eT+D,which was compensated by an increased expression of rbcL,psaA,CAB,and especially PGR5,i.e.,genes encoding Rubisco large subunit and PSI components:apoproteins A,chlorophyll a/b-associated protein(CAB)of light-harvesting complex,and proton gradient regulation 5(PGR5)protein of the main pathway of cyclic electron transport(CET)around PSI.In C_(4)species,the protective MDH complex was expressed to a lesser extent,but activation of the C_(4)carbon-concentrating mechanism(CCM)and upregulation of PGR5 expression were observed,particularly under the individual action of the factors.Under the combined stress of eT+D,C.crassa exhibited a synergistic effect,where the increase in NPQ level and NAD-ME activity,as well as decrease in NADP-ME activity was less pronounced compared with the effect of singular factors.Comparative physiological,biochemical,and molecular analyses of how C_(3)and C_(4)species response to individual and combined climatic factors provide new insights into sustainable plant adaptation strategies in the face of global climate change.Considering the high nutritional value of these two fodder species,a technological approach could be developed to improve the productivity of salt affected lands. 展开更多
关键词 Atriplex verrucifera M.bied. Climacoptera crassa(M.bieb.)Botsch. CHENOPODIACEAE photosynthesis cyclic electron transport(CET) malate valves arid land
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Research on the"Stomach-Knee Axis"and the Practice of"Stomach and Knee Joint Treatment"Based on the"Combined Bi of Body Constituents and Zang Organs"Theory
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作者 Xiaoqiang ZHANG Wenjing LU Peifang LI 《Medicinal Plant》 2026年第1期34-39,共6页
The existence of the"stomach-knee axis"and the potential independent association between"Helicobacter pylori(Hp)infection and knee osteoarthritis(KOA)"have been substantiated through multiple lines... The existence of the"stomach-knee axis"and the potential independent association between"Helicobacter pylori(Hp)infection and knee osteoarthritis(KOA)"have been substantiated through multiple lines of evidence,including epidemiological studies of the"stomach-knee axis",investigations into the pathological mechanisms linking"Hp infection and arthritis",as well as research on co-treatment drugs and the anti-inflammatory mechanisms relevant to"gastritis and arthritis".The investigation into"stomach and knee joint treatment"is grounded in the concept that the"stomach-knee axis"aligns with the"combined bi of body constituents and zang organs"theory.Clinical cases have demonstrated that therapeutic strategies of"stomach and knee joint treatment"can mitigate KOA damage by modulating the"stomach-knee axis"and eradicating Hp infection in the stomach.This study aims to contribute novel insights into the cross-system treatment of KOA.Further investigation into the"stomach-knee axis"may yield innovative strategies for the prevention and management of KOA,potentially through the eradication of Hp. 展开更多
关键词 STOMACH KNEE Helicobacter pylori(Hp) Knee osteoarthritis(KOA) Combined bi of body constituents and zang organs Stomach and knee joint treatment
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基于MRI影像组学模型对BI-RADS 4类乳腺肿块的诊断价值分析
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作者 王肖肖 梁长华 +2 位作者 郭利茹 田方 孙运帮 《中国医学装备》 2026年第2期52-57,共6页
目的:探讨磁共振成像(MRI)影像组学模型对乳腺影像报告和数据系统(BI-RADS)4类乳腺肿块的诊断价值。方法:回顾性选取2023年2月至2025年2月中国人民解放军第八十三集团军医院及河南医药大学第一附属医院收治的157例BI-RADS 4类乳腺肿块患... 目的:探讨磁共振成像(MRI)影像组学模型对乳腺影像报告和数据系统(BI-RADS)4类乳腺肿块的诊断价值。方法:回顾性选取2023年2月至2025年2月中国人民解放军第八十三集团军医院及河南医药大学第一附属医院收治的157例BI-RADS 4类乳腺肿块患者,根据乳腺肿块性质将其分为良性组(33例)和恶性组(124例)。提取乳腺肿块853项MRI影像组学特征,采用Mann-Whitney U检验筛选良恶性肿块间差异显著的特征,通过分层随机抽样法以7∶3比例,将157例BI-RADS 4类乳腺肿块患者分为训练集(110例)和测试集(47例),构建MRI多维度影像组学logistic回归模型(简称影像组学模型)。依据BI-RADS 4类恶性风险差异,将157例患者分为4A组(89例,恶性风险为2%~10%)、4B组(45例,恶性风险10%~50%)和4C组(23例,恶性风险50%~95%)3个亚组,在测试集验证影像组学模型的诊断效能,并与传统BI-RADS分类影像组学诊断方法进行对比,采用受试者工作特征(ROC)曲线下面积(AUC)分析3个亚组的诊断效能。结果:筛选出56项差异显著特征,最终构建的模型独立预测10项乳腺肿块良恶性的独立影像组学特征。影像组学模型在测试集中的AUC为0.941,显著高于BI-RADS分类的0.785,差异有统计学意义(Z=3.856,P<0.001),影像组学模型的灵敏度、特异度和准确率分别为92.7%、84.8%和90.4%。3个亚组分析显示,影像组学模型在恶性风险的4A、4B和4C组中AUC分别为0.938、0.945和0.951,均>0.93,4C组准确率为95.7%,阳性预测值为100%。结论:MRI影像组学模型对BI-RADS 4类乳腺肿块具有较高诊断效能,尤其在高风险诊断中表现优异,可为临床精准鉴别提供参考。 展开更多
关键词 乳腺肿块 乳腺影像报告和数据系统(bi-RADS)4类 磁共振成像(MRI) 影像组学 诊断
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时效时间和Sb添加对Sn-9Zn-3Bi/Cu焊点界面金属间化合物生长行为的影响 被引量:2
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作者 涂文斌 胡志华 +3 位作者 邹雨柔 刘冠鹏 王善林 陈玉华 《材料导报》 北大核心 2025年第6期189-194,共6页
无铅钎料焊点界面金属间化合物是影响焊点可靠性的重要因素。本工作采用扫描电镜研究了时效时间和Sb添加对Sn-9Zn-3Bi/Cu焊点界面金属间化合物形貌及生长动力学的影响。结果表明:随着时效时间的延长,Sn-9Zn-3Bi/Cu焊点界面金属间化合物... 无铅钎料焊点界面金属间化合物是影响焊点可靠性的重要因素。本工作采用扫描电镜研究了时效时间和Sb添加对Sn-9Zn-3Bi/Cu焊点界面金属间化合物形貌及生长动力学的影响。结果表明:随着时效时间的延长,Sn-9Zn-3Bi/Cu焊点界面金属间化合物厚度逐渐增加,Sn-9Zn-3Bi/Cu焊点界面金属间化合物为γ-Cu_(5)Zn_(8)相。Sb添加会减小长时效后的Sn-9Zn-3Bi/Cu焊点界面金属间化合物厚度,其生长系数从0.67μm/h^(1/2)降至0.56μm/h^(1/2)。随着时效时间延长至168 h,焊点界面金属间化合物除了γ-Cu_(5)Zn_(8)相外,还会在靠近Cu基板处形成Cu_(6)Sn_(5)相和靠近钎料侧形成扩散反应层,Sb元素会扩散到焊点界面处Cu_(6)Sn_(5)相中,以固溶体形式存在。 展开更多
关键词 时效时间 Sb添加 Sn-9Zn-3bi钎料 界面组织 生长系数
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BIS指导下丙泊酚闭环靶控输注麻醉方式用于机器人辅助胰十二指肠切除术的效果研究
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作者 谭文君 邢斌瑜 +2 位作者 郭嘉雯 路璐 朱皓阳 《机器人外科学杂志(中英文)》 2025年第12期2060-2065,共6页
目的:分析以脑电双频指数(BIS)为指导的丙泊酚闭环靶控输注麻醉在机器人辅助胰十二指肠切除术中的临床应用效果。方法:回顾性选取2023年10月—2024年11月于西安交通大学第一附属医院接受机器人辅助胰十二指肠切除术的102例患者作为研究... 目的:分析以脑电双频指数(BIS)为指导的丙泊酚闭环靶控输注麻醉在机器人辅助胰十二指肠切除术中的临床应用效果。方法:回顾性选取2023年10月—2024年11月于西安交通大学第一附属医院接受机器人辅助胰十二指肠切除术的102例患者作为研究对象,根据麻醉方式不同分为对照组(n=51,采用丙泊酚开环输注麻醉)和研究组(n=51,采用BIS指导的丙泊酚闭环靶控输注麻醉)。比较两组患者围手术期指标、血流动力学指标、认知功能及不良反应发生率。结果:研究组麻醉维持时长、苏醒时长、拔管时间、自主呼吸恢复时间均显著短于对照组,丙泊酚用量显著少于对照组,术后24 h疼痛评分显著低于对照组(P<0.05)。两组患者麻醉诱导前(T0)、研究组闭环系统开启前/对照组丙泊酚输注30 min后(T1)的心率、平均动脉压比较,差异无统计学意义(P>0.05);研究组闭环系统开启后1 h/对照组丙泊酚输注1.5 h后(T2),研究组心率低于对照组,平均动脉压高于对照组;术毕即刻(T3),研究组心率低于对照组、平均动脉压高于对照组(P<0.05)。术前1 d两组简易精神状态量表(MMSE)评分无显著差异(P>0.05),术后1 d、3 d研究组MMSE评分显著高于对照组(P<0.05)。研究组不良反应发生率低于对照组(P<0.05)。结论:BIS指导下丙泊酚闭环靶控输注麻醉方式可加快机器人辅助胰十二指肠切除术后患者康复进程,减少丙泊酚用量,稳定血流动力学,改善术后认知功能,降低不良反应发生率。 展开更多
关键词 biS值 丙泊酚 闭环靶控输注 机器人辅助手术 胰十二指肠切除术
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Structure of Bi_2O_3-ZnO-B_2O_3 system low-melting sealing glass 被引量:7
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作者 何峰 程金树 +1 位作者 邓大伟 王俊 《Journal of Central South University》 SCIE EI CAS 2010年第2期257-262,共6页
Bi2O3-ZnO-B2O3 system glass is a kind of lead-free low melting sealing glasses. The structure of Bi2O3-ZnO-B2O3 system low-melting sealing glass was investigated by DSC, FT-IR, XRD and SEM. The results show that with ... Bi2O3-ZnO-B2O3 system glass is a kind of lead-free low melting sealing glasses. The structure of Bi2O3-ZnO-B2O3 system low-melting sealing glass was investigated by DSC, FT-IR, XRD and SEM. The results show that with the increase of B2O3 content, the transition temperature Tg and softening temperature Tf of Bi2O3-ZnO-B2O3 system low-melting sealing glasses increase, which leads to the liquid phase precipitation temperature increasing and promotes the structure stability in the glass. With increasing the heat treatment temperature, a large number of liquid phases appear in samples and the sinter efficiency of the samples increases. The FT-IR spectra of the glasses show the presence of some bands that are assigned to vibrations of Bi--O bond from [BO3] pyramidal and [BiO6] octahedral units and B--O from [BO3] and [BO4] units. With the decrease of B203 content, the crystallization tendency of the glass increases. In glass samples Bl and B〉 crystallization starts at 460 ℃ and 540 ℃, respectively. Both of them precipitate Bi24B2O39 phases. 展开更多
关键词 bi2O3-ZnO-B2O3 system glass low-melting sealing glass transition temperature softening temperature
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Performance characterization of Bi_2O_3/Al nanoenergetics blasted micro-forming system 被引量:2
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作者 Vinay Kumar Patel Rishi Kant +2 位作者 Anu choudhary Madhusudan Painuly Shantanu Bhattacharya 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2019年第1期98-105,共8页
This paper reports a novel micro-blast driven manufacturing process for micro-forming of Aluminum foils. The micro-blast is realized by using a nanoenergetic material system comprising of Bi_2O_3 microrods and aluminu... This paper reports a novel micro-blast driven manufacturing process for micro-forming of Aluminum foils. The micro-blast is realized by using a nanoenergetic material system comprising of Bi_2O_3 microrods and aluminum particles. There is an enhanced need of forming of thin aluminum foil structures in small regions from point of view of drug packaging etc. The process developed caters to this need by using a single shot forming process using a micro-blast source. The micro-blast that is generated from an energetic composite system is made highly tunable by modulating the peak pressure generated through the blasting process and their impact in micro-forming of thin aluminum foils is observed through parametric studies. The engineering challenge involved in these experiments is to tune the blast pressure properties in order to address the forming of thin metal sheets with limiting boundary values as defined by the failure criteria. A variety of characterization techniques related to a thorough analysis of the synthesized material viz. X-ray diffraction(XRD), Scanning Electron Microscopy(SEM) etc, are used to tune the functional properties like gauge blast pressure etc, of material system. We have found a material system that can generate a maximum peak pressure of 73.8 MPa with pressurization rate of 2460 GPas^(-1) and that is able to accomplish micro-forming on thin metal foils(around 0.3 mm thickness). Experimental investigations demonstrate that tunabilty aspect of the energetic composites when exercised can enable variant processes such as embossing, coining, drilling etc. which may be of significant utility to drug packaging industries. A proper mathematical modeling of the forming process and critical process parameters therein have also been detailed. 展开更多
关键词 MICROFORMING ALUMINUM FOIL bi2O3 Nanoenergetic TUNAbiLITY Process parameters
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Bi基光催化剂用于CO_(2)还原的研究进展 被引量:1
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作者 李蓉蓉 黄文斌 +3 位作者 贾亦静 刘昊然 魏强 周亚松 《精细化工》 北大核心 2025年第8期1638-1652,共15页
光催化CO_(2)还原是缓解能源危机、减少CO_(2)排放的理想低碳绿色技术,该技术的核心是高活性光催化剂的开发。近年来,Bi基光催化剂因其带隙窄、光激发效率高等优点而受到国内外学者的广泛关注。该文综述了Bi基光催化剂用于CO_(2)还原的... 光催化CO_(2)还原是缓解能源危机、减少CO_(2)排放的理想低碳绿色技术,该技术的核心是高活性光催化剂的开发。近年来,Bi基光催化剂因其带隙窄、光激发效率高等优点而受到国内外学者的广泛关注。该文综述了Bi基光催化剂用于CO_(2)还原的研究进展。简单介绍了光催化剂催化CO_(2)还原的基本原理、用于CO_(2)还原的Bi基光催化剂的种类。着重总结了Bi基光催化剂的改性方法,包括形貌调控、掺杂、引入缺陷、负载助催化剂、晶面调控和构建异质结。对不同改性方法对光催化CO_(2)还原性能进行了深入分析,阐明了光催化机理,并展望了Bi基光催化剂的应用前景。 展开更多
关键词 bi基催化剂 光催化 表面改性 CO_(2)还原 制备
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基于同步辐射小角X射线散射(SAXS)的水系锂离子电池Bi_(2)O_(3)负极材料在充放电过程中的结构研究 被引量:1
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作者 吴昭君 赵梦媛 +3 位作者 张意浛 姜瑶 程伟东 邢雪青 《中国无机分析化学》 北大核心 2025年第11期1878-1889,共12页
锂离子电池由于其能量密度高被认为是储能系统的最佳选择之一。然而由于锂离子电池中有机电解液产生的燃烧爆炸等安全问题,使其应用范围受到极大限制。水系锂离子电池的电解液为水溶液,安全性较高,有望成为新能源领域的重要组成部分。B... 锂离子电池由于其能量密度高被认为是储能系统的最佳选择之一。然而由于锂离子电池中有机电解液产生的燃烧爆炸等安全问题,使其应用范围受到极大限制。水系锂离子电池的电解液为水溶液,安全性较高,有望成为新能源领域的重要组成部分。Bi基材料被认为是锂离子电池负极材料中最有潜力的可选材料之一。采用溶剂热法合成了Bi-MOF前驱体,通过控制煅烧温度成功制备了具有多级纳米结构的Bi_(2)O_(3)材料,并对其进行了相关的结构表征和性能测试。利用同步辐射小角X射线散射(SAXS)技术对Bi_(2)O_(3)-520负极材料在水系锂离子电池中的结构演变进行原位观测,揭示了其在充放电过程中存在的多级纳米结构及各级纳米粒子异质性演化行为,这种多级结构演变特性为理解水系锂离子电池Bi基负极材料的储能机制提供了新的结构视角。同步辐射SAXS技术(包括同步辐射联用技术)为探究水系锂离子电池在充放电过程中其结构演变和电化学性能之间的构效关系提供了重要的科学依据和手段。 展开更多
关键词 bi基负极材料 水系锂离子电池 小角X射线散射 纳米结构
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