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金属热处理中的一种可控气氛─—加压氨分解技术 被引量:1
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作者 奚永龙 张祀良 《低温工程》 CAS CSCD 1995年第3期31-35,共5页
介绍了金属光亮热处理中一种可控保护气氛新的制备方法─—加压氨分解技术。与其它制备方法相比,加压氨分解制取的氢氮混合气可直接与变压吸附法制得的氮气混合,无须另设加压设备。而且,氢气浓度可在0.1%~40%(体积)范围内... 介绍了金属光亮热处理中一种可控保护气氛新的制备方法─—加压氨分解技术。与其它制备方法相比,加压氨分解制取的氢氮混合气可直接与变压吸附法制得的氮气混合,无须另设加压设备。而且,氢气浓度可在0.1%~40%(体积)范围内调节控制。本方法投资费用低,能耗小,操作方便。 展开更多
关键词 全属光亮热处理 可控气氛 氨分解 加压.
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起重机金属结构锈蚀寿命期的快速估算 被引量:1
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作者 程文明 《铁道货运》 1994年第6期21-23,共3页
针对现场使用需要,从理论上推导了起重机金属结构锈蚀后剩余使用寿命的快速估算公式。文中计算实例表明,此法简便、实用。
关键词 起重机 全属结构 锈蚀 寿命
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冷段管道监督检查方法及缺陷处理措施 被引量:4
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作者 高志军 《华北电力技术》 CAS 北大核心 2003年第5期37-39,共3页
张家口发电厂2台国产300 MW机组冷段管道弯头及焊口,在2002年大修中发现多处表面裂纹和重皮缺陷。为此对其表面裂纹产生的原因进行了分析,阐述了加强火电厂冷段管道金属监督检查的必要性,并在实践中总结了冷段管道金属监督检查的方法以... 张家口发电厂2台国产300 MW机组冷段管道弯头及焊口,在2002年大修中发现多处表面裂纹和重皮缺陷。为此对其表面裂纹产生的原因进行了分析,阐述了加强火电厂冷段管道金属监督检查的必要性,并在实践中总结了冷段管道金属监督检查的方法以及对发现的管道缺陷进行处理的技术措施。 展开更多
关键词 火力发电厂 冷段管道 监督检查方法 缺陷处理 裂纹 全属监督
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Investigation of Heavy Metal Contents in Traditional Chinese Herbal Medicine Peristrophe roxburghiana Collected from Northwest of Guangxi 被引量:2
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作者 刘旭辉 李容 +2 位作者 郭俊 罗志勇 覃勇荣 《Agricultural Science & Technology》 CAS 2016年第12期2751-2756,2762,共7页
Objective] This study was conducted to evaluate the product quality and safety of Peristrophe roxburghiana_ col ected from different places in Hechi City, northwest of Gunagxi, so as to provide basic data for further ... Objective] This study was conducted to evaluate the product quality and safety of Peristrophe roxburghiana_ col ected from different places in Hechi City, northwest of Gunagxi, so as to provide basic data for further development and uti-lization of the characteristic plant resource P. roxburghiana. [Method] Contents of 9 kinds of heavy metals including Cd, Mn, Pb, Zn and Cu in the herb were deter-mined by the method of wet digestion-flame atomic absorption spectrophotometry and atomic fluorescence spectrometry, respectively. [Results] Heavy metal contents of Cd, Mn, Pb, Fe, Cu, Zn, As, Hg and Se were 1.62-17.25, 8.93-142.53, 4.37-18.43, 103.7-242.81, 2.55-5.35, 85.40-146.30, 0.07-0.54, 0.00-0.08 and 0.00-0.47 mg/kg, respectively. According to the national food safety standards and Green Trade Standards of lmporting &amp; Exporting Medicinal plants &amp; Preparations, the heavy metal contents of the P. roxburghiana_samples col ected from different coun-ties in Hechi City exceeded standards or at the critical values. Among which, Cd, Pb and Zn contents of the samples are seriously higher than the standards. [Con-clusion] Therefore, the impact of soil heavy metal pol ution on the safety of edible plants in the northwest of Guangxi should be highly concerned. 展开更多
关键词 Northwest of Guangxi Traditional Chinese herbal medicine Peristro-pheroxburghiana Product quality and safety Heavy metal content
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无机化学和有机化学的桥梁——金属有机化学 被引量:4
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作者 高靓 《化工管理》 2015年第17期58-58,共1页
文中首先阐述了金属有机化学过去一百年来的发展历程,然后从三个反面解释了金属有机化学近年来得到快速发展的原因,最后分别从金属化合有机物的结构、物理化学性质、有机新反应和其它用途叙述了金属有机化学的现状。
关键词 金属有机化学 稀有全属 原子结构 反应机理
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微生物修复技术在重金属污染治理中的应用研究 被引量:5
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作者 詹敬江 《资源节约与环保》 2017年第3期22-22,24,共2页
随着经济的发展,我国的城市现代化进程不断加快,工业、交通、生活垃圾等的排放量也随之增加。这些排放物中有很多重金属污染物,其很难被分解,最终沉积于环境当中,威胁着人类的身体健康。近年来,科学家研究发现,微生物修复治理重金属污... 随着经济的发展,我国的城市现代化进程不断加快,工业、交通、生活垃圾等的排放量也随之增加。这些排放物中有很多重金属污染物,其很难被分解,最终沉积于环境当中,威胁着人类的身体健康。近年来,科学家研究发现,微生物修复治理重金属污染具有低成本、高效率、无二次污染等优势,利于改善生态环境,具有良好的应用前景。为此,本文就微生物修复技术在重金属污染治理中的应用做了进一步的研究。 展开更多
关键词 微生物修复技术 全属污染 治理 研究进展
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水暖管道腐蚀原因与预防措施
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作者 杜永权 《黑龙江科学》 2014年第9期35-35,共1页
水暖管道由于其特殊性,导致了其在使用的过程中经常出现被腐蚀的现象,腐蚀后的水暖管道经常出现泄漏事故,给人们的生产生活带来了不便。为了较好地预防和处理金属给排水管道的腐蚀问题,从给排水工程施工的过程中水暖管道出现腐蚀的原因... 水暖管道由于其特殊性,导致了其在使用的过程中经常出现被腐蚀的现象,腐蚀后的水暖管道经常出现泄漏事故,给人们的生产生活带来了不便。为了较好地预防和处理金属给排水管道的腐蚀问题,从给排水工程施工的过程中水暖管道出现腐蚀的原因入手,分析了给排水工程施工过程中出现的水暖金属管道被腐蚀的现象,并对相应的问题提出了解决措施。 展开更多
关键词 水暖管道 全属腐蚀 预防措施
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五年来我国有色金属工业结构调整状况及对策建议 被引量:2
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作者 赵武壮 陈维胜 《世界有色金属》 2003年第2期10-14,共5页
本文总结了近5年来我国有色金属工业结构调整和产业升级的基本情况,即中国有色金属工业集约化程度、技装备水平提高,生产成本下降,行业整体实力增强。而这些成绩的取得都有赖于国家积极的财政政策及“债转股”政策的推动,有赖于深化企... 本文总结了近5年来我国有色金属工业结构调整和产业升级的基本情况,即中国有色金属工业集约化程度、技装备水平提高,生产成本下降,行业整体实力增强。而这些成绩的取得都有赖于国家积极的财政政策及“债转股”政策的推动,有赖于深化企业改革及发挥市场资源配置的作用等等。同时,针对对当前及今后有色金属工业结构调整和产业结构升级所面临的问题。 展开更多
关键词 有色全属工业 结构调整 中国 企业改革 资源配置 产业结构
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土壤重金属及农药污染对农作物的影响研究 被引量:1
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作者 曹志玲 《新农村(黑龙江)》 2017年第9期145-145,共1页
随着工农业的发展,环境中的污染物正趋于多元化和复杂化.土壤重金属和农药的污染是目前科学领域研究的热点。本文分别对农药和重金属在农业生态环境中的污染进行综合分析,在此基础上,提出土壤污染防治方案,为土壤环境保护与农业可... 随着工农业的发展,环境中的污染物正趋于多元化和复杂化.土壤重金属和农药的污染是目前科学领域研究的热点。本文分别对农药和重金属在农业生态环境中的污染进行综合分析,在此基础上,提出土壤污染防治方案,为土壤环境保护与农业可持续发展提供依据。 展开更多
关键词 土壤 全属 农药 修复技术
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快速发展中的中国有色金属市场
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作者 朱光 《有色金属工业》 2004年第7期21-22,共2页
关键词 中国 有色金属市场 有色金属工业 经济增长 经济发展 上海全属交易所 期货交易
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电信传输原理
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《中国数据通信》 2004年第9期122-122,共1页
关键词 《电信传输原理》 书评 全属传输线 波导传输线 光纤传输线
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小企业中高技术的应用
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作者 陈云卿 《管理观察》 1998年第11期21-21,共1页
关键词 小企业 高技术 采用新技术 自动化系统 高技术企业 数控机床 美国东部地区 高精度 提高产品质量 全属结构
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依靠科学技术促进重庆工业支柱产业结构调整
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《重庆经济》 1995年第6期25-30,共6页
关键词 科学技术 重庆 工业支柱产业 产业结构 结构调整 汽车工业 重大机械装奋制造业 全属材料工业 化学工业 医药工业 建材工业
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Alloy gene Gibbs energy partition function and equilibrium holographic network phase diagrams of AuCu_3-type sublattice system 被引量:3
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作者 谢佑卿 李小波 +2 位作者 刘心笔 聂耀庄 彭红建 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第11期3585-3610,共26页
Taking AuCu3-type sublattice system as an example, three discoveries have been presented: First, the third barrier hindering the progress in metal materials science is that researchers have got used to recognizing exp... Taking AuCu3-type sublattice system as an example, three discoveries have been presented: First, the third barrier hindering the progress in metal materials science is that researchers have got used to recognizing experimental phenomena of alloy phase transitions during extremely slow variation in temperature by equilibrium thinking mode and then taking erroneous knowledge of experimental phenomena as selected information for establishing Gibbs energy function and so-called equilibrium phase diagram. Second, the equilibrium holographic network phase diagrams of AuCu3-type sublattice system may be used to describe systematic correlativity of the composition?temperature-dependent alloy gene arranging structures and complete thermodynamic properties, and to be a standard for studying experimental subequilibrium order-disorder transition. Third, the equilibrium transition of each alloy is a homogeneous single-phase rather than a heterogeneous two-phase, and there exists a single-phase boundary curve without two-phase region of the ordered and disordered phases; the composition and temperature of the top point on the phase-boundary curve are far away from the ones of the critical point of the AuCu3 compound. 展开更多
关键词 AuCu3 compound AuCu3-type sublattice system alloy gene Gibbs energy partition function equilibrium holographic network phase diagram systematic metal materials science
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Adaptively Secure Attribute-Based Encryption Supporting Attribute Revocation 被引量:2
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作者 Wu Qiuxin Zhang Miao 《China Communications》 SCIE CSCD 2012年第9期22-40,共19页
Attribute revocation is inevitable and al- so important for Attribute-Based Encryption (ABE) in practice. However, little attention has been paid to this issue, and it retrains one of the rmin obsta-cles for the app... Attribute revocation is inevitable and al- so important for Attribute-Based Encryption (ABE) in practice. However, little attention has been paid to this issue, and it retrains one of the rmin obsta-cles for the application of ABE. Most of existing ABE schemes support attribute revocation work under indirect revocation model such that all the users' private keys will be affected when the revo-cation events occur. Though some ABE schemes have realized revocation under direct revocation model such that the revocation list is embedded in the ciphertext and none of the users' private keys will be affected by revocation, they mostly focused on the user revocation that revokes the user's whole attributes, or they can only be proven to be selectively secure. In this paper, we first define a model of adaptively secure ABE supporting the at- tribute revocation under direct revocation model. Then we propose a Key-Policy ABE (KP-ABE) scheme and a Ciphertext-Policy ABE (CP-ABE) scheme on composite order bilinear groups. Finally, we prove our schemes to be adaptively secure by employing the methodology of dual system eno cryption. 展开更多
关键词 ABE direct revocation model attributerevocation adaptive security dual system encryp-tion access structure
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Alloy gene Gibbs energy partition function and equilibrium holographic network phase diagrams of Au_3Cu-type sublattice system 被引量:3
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作者 谢佑卿 聂耀庄 +2 位作者 李小波 彭红建 刘心笔 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第1期211-240,共30页
Taking Au3Cu-type sublattice system as an example, three discoveries have been presented. First, the fourth barrier to hinder the progress of metal materials science is that today’s researchers do not understand that... Taking Au3Cu-type sublattice system as an example, three discoveries have been presented. First, the fourth barrier to hinder the progress of metal materials science is that today’s researchers do not understand that the Gibbs energy function of an alloy phase should be derived from Gibbs energy partition function constructed of alloy gene sequence and their Gibbs energy sequence. Second, the six rules for establishing alloy gene Gibbs energy partition function have been discovered, and it has been specially proved that the probabilities of structure units occupied at the Gibbs energy levels in the degeneracy factor for calculating configuration entropy should be degenerated as ones of component atoms occupied at the lattice points. Third, the main characteristics unexpected by today’s researchers are as follows. There exists a single-phase boundary curve without two-phase region coexisting by the ordered and disordered phases. The composition and temperature of the top point on the phase-boundary curve are far away from those of the critical point of the Au3Cu compound; At 0 K, the composition of the lowest point on the composition-dependent Gibbs energy curve is notably deviated from that of the Au3Cu compounds. The theoretical limit composition range of long range ordered Au3Cu-type alloys is determined by the first jumping order degree. 展开更多
关键词 Au3Cu compound Au3Cu-type sublattice system alloy gene Gibbs energy partition function equilibrium holographic network phase diagrams systematic metal materials science
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An attribute recognition model for safe thickness assessment between concealed karst cave and tunnel 被引量:12
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作者 HUANG Xin LI Shu-cai +5 位作者 XU Zhen-hao GUO Ming SHI Xue-song GAO Bin ZHANG Bo LIU Lang 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第4期955-969,共15页
An attribute recognition model for safe thickness assessment between a concealed karst cave and a tunnel is established based on the attribute mathematic theory.The model can be applied to carrying out risk classifica... An attribute recognition model for safe thickness assessment between a concealed karst cave and a tunnel is established based on the attribute mathematic theory.The model can be applied to carrying out risk classification of the safe thickness between a concealed karst cave and a tunnel and to guarantee construction’s safety in tunnel engineering.Firstly,the assessment indicators and classification standard of safe thickness between a concealed karst cave and a tunnel are studied based on the perturbation method.Then some attribute measurement functions are constructed to compute the attribute measurement of each single index and synthetic attribute measurement.Finally,the identification and classification of risk assessment of safe thickness between a concealed karst cave and a tunnel are recognized by the confidence criterion.The results of two engineering application show that the evaluation results agree well with the site situations in construction.The results provide a good guidance for the tunnel construction. 展开更多
关键词 concealed karst cave karst tunnel safe thickness attribute recognition method
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Dual-Work-Function Ni-FUSI Metal Gate for CMOS Technology
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作者 周华杰 徐秋霞 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第10期1532-1539,共8页
This paper investigates the work function adjustment of a full silicidation (Ni-FUSI) metal gate. It is found that implanting dopant into poly-Si before silicidation can modulate the work function of a Ni-FUSI metal... This paper investigates the work function adjustment of a full silicidation (Ni-FUSI) metal gate. It is found that implanting dopant into poly-Si before silicidation can modulate the work function of a Ni-FUSI metal gate efficiently. With the implantation of p-type or n-type dopants,such as BF2 ,As,and P,the work function of a Ni-FUSI metal gate can be made higher or lower to satisfy the requirement of pMOS or nMOS, respectively. But implanting a high dose of As into a poly-Si gate before silicidation will cause the delamination effect and EOT loss,and thus As dopant is not suitable to be used to adjust the work function of a Ni-FUSI metal gate. Due to the EOT reduction in the FUSI Process,the gate leakage current of a FUSI metal gate capacitor is larger than that of a poly-Si gate capacitor. 展开更多
关键词 metal gate FUSI SILICIDE
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Holographic alloy positioning design system and holographic network phase diagrams of Au-Cu system 被引量:3
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作者 谢佑卿 刘心笔 +2 位作者 李小波 彭红建 聂耀庄 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第3期885-906,共22页
Taking Au?Cu system as an example, three discoveries and two methods were presented. First, a new way for boosting sustainable progress of systematic metal materials science (SMMS) and alloy gene engineering (AGE) is ... Taking Au?Cu system as an example, three discoveries and two methods were presented. First, a new way for boosting sustainable progress of systematic metal materials science (SMMS) and alloy gene engineering (AGE) is to establish holographic alloy positioning design (HAPD) system, of which the base consists of measurement and calculation center, SMMS center, AGE center, HAPD information center and HAPD cybernation center; Second, the resonance activating-sychro alternating mechanism of atom movement may be divided into the located and oriented diffuse modes; Third, the equilibrium and subequilibrium holographic network phase diagrams are blueprints and operable platform for researchers to discover, design, manufacture and deploy advanced alloys, which are obtained respectively by the equilibrium lever numerical method and cross point numerical method of isothermal Gibbs energy curves. As clicking each network point, the holographic information of three structure levels for the designed alloy may be readily obtained: the phase constitution and fraction, phase arranging structure and properties of organization; the composition, alloy gene arranging structure and properties of each phase and the electronic structures and properties of alloy genes. It will create a new era for network designing advanced alloys. 展开更多
关键词 Au-Cu system holographic alloy positioning design system equilibrium and subequilibrium holographic network phase diagrams systematic metal materials science network designing advanced alloys
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EBS-Based Collusion Resistant Group Key Management Using Attribute-Based Enc ryption 被引量:1
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作者 Chen Yanli Yang Geng 《China Communications》 SCIE CSCD 2012年第1期92-101,共10页
The m ajor advantages of EBS-based key rrkanagerrent scheme are its enhanced network survivability, high dynamic performance, and better support for network expansion. But it suffers from the collusion problem, which ... The m ajor advantages of EBS-based key rrkanagerrent scheme are its enhanced network survivability, high dynamic performance, and better support for network expansion. But it suffers from the collusion problem, which means it is prone to the cooperative attack of evicted members. A novel EBS-based collusion resistant group management scheme utilizing the construction of Ciphertext-Policy Attribute-Based Encryption (CP-ABE) is proposed. The new scheme satisfies the desired security properties, such as forward secrecy, backward secrecy and collusion secrecy. Compared with existing EBS-based key rmnagement scheme, the new scheme can resolve EBS collusion problem completely. Even all evicted members work together, and share their individual piece of information, they could not access to the new group key. In addition, our scheme is more efficient in terms of conmnication and computation overhead when the group size is large. It can be well controlled even in the case of large-scale application scenarios. 展开更多
关键词 group key management exclusion basis systems attribute-based encryption collusionres is tant
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