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烧结工艺对UN-30%U_(3)Si_(2)芯块的致密化影响研究
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作者 粟丹科 潘小强 +3 位作者 陆永洪 杨静 王挺 段苗苗 《核动力工程》 北大核心 2025年第1期175-182,共8页
本文基于粉末冶金技术制备了UN-30%U_(3)Si_(2)复合燃料芯块(U_(3)Si_(2)质量百分数为30%),研究了烧结气氛、烧结温度、烧结时间等烧结工艺对芯块烧结密度的影响规律,主要通过芯块的化学成分、物相组成以及微观组织变化等方面进行致密... 本文基于粉末冶金技术制备了UN-30%U_(3)Si_(2)复合燃料芯块(U_(3)Si_(2)质量百分数为30%),研究了烧结气氛、烧结温度、烧结时间等烧结工艺对芯块烧结密度的影响规律,主要通过芯块的化学成分、物相组成以及微观组织变化等方面进行致密化过程分析。结果表明,UN-30%U_(3)Si_(2)复合燃料芯块真空烧结相比氩气气氛烧结更有利于致密化;随着烧结温度(1600~1675℃)升高,致密度逐渐增加,最高可达97%T.D.(T.D.为理论密度);当烧结温度高于U_(3)Si_(2)熔点之后,随着温度上升,U_(3)Si_(2)相在高真空条件下会烧损挥发,并且N元素有向U_(3)Si_(2)相扩散的趋势,形成未知USi_(x)N_(y)相;烧结温度的升高或者烧结时间的延长,均有利于U3Si2相对UN相形成包覆。 展开更多
关键词 un-30%U_3Si_2复合燃料 烧结工艺 致密化过程
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UN-U_(3)Si_(2)复合芯块放电等离子体烧结制备工艺与性能表征研究
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作者 孙启明 姬鹏波 +3 位作者 王纪钧 曹军文 李昱 李宗书 《原子能科学技术》 北大核心 2025年第S2期340-347,共8页
为进一步提升核燃料的安全性和可靠性,本文以UN-U_(3)Si_(2)复合芯块为研究对象,采用放电等离子体烧结技术,结合微观形貌观察、化学成分测试、热物理和力学性能测量等表征方法开展系统研究。通过正交试验研究了烧结温度、保温时间、烧... 为进一步提升核燃料的安全性和可靠性,本文以UN-U_(3)Si_(2)复合芯块为研究对象,采用放电等离子体烧结技术,结合微观形貌观察、化学成分测试、热物理和力学性能测量等表征方法开展系统研究。通过正交试验研究了烧结温度、保温时间、烧结压力对复合芯块致密度的影响,通过UN和U_(3)Si_(2)粉末不同粒径之间的组合,研究粉末粒径对复合芯块致密度的影响,通过调整混合比例,研究不同U_(3)Si_(2)含量对复合芯块的热导率、硬度和抗压强度等性能的影响。结果表明,UN-20%U_(3)Si_(2)复合芯块最佳烧结参数为:烧结温度1650℃、保温时间30 min、烧结压力50 MPa,制备得到的复合芯块密度为13.60 g/cm^(3),相对密度为98.30%,3种因素对复合芯块密度影响的显著程度为烧结温度>烧结压力>保温时间。细UN-粗U3Si2制备的UN-20%U_(3)Si_(2)复合芯块的密度最大,为13.60 g/cm^(3),相对密度为98.31%。UN-20%U_(3)Si_(2)的复合芯块综合性能最优,热导率达到29.0 W/(m·K)@900℃,热膨胀系数达到8.90×10^(-6)K^(-1)@600℃,硬度为637 HV1,抗压强度为331.0 MPa。本文的试验结果能够为后续UN-U_(3)Si_(2)复合芯块的研究和应用提供一定的基础。 展开更多
关键词 un-U_(3)Si_(2)复合芯块 放电等离子体烧结 热物理性能 力学性能
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短小芽胞杆菌(Bacillus pumilus UN-31-C-42)对青海藏系羊蹄脱毛效果研究 被引量:1
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作者 张红见 赵静 张虎 《食品研究与开发》 CAS 北大核心 2010年第8期167-169,共3页
通过L9(34)正交试验确定产脱毛蛋白酶菌株Bacillus pumilus UN-31-C-42的最佳产酶条件为:温度34℃,pH值7.0,发酵时间48h;结果表明该菌株对藏系羊蹄具有良好的脱毛效果,最佳脱毛时间为24h。
关键词 短小芽胞杆菌un-31-C-42 蛋白酶 发酵条件 藏系羊蹄 脱毛
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UN-500全自动尿沉渣分析仪故障处理 被引量:2
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作者 杨晓冬 林桂花 《医疗装备》 2016年第14期48-48,共1页
1尿沉渣检验的临床价值尿液是机体内的重要排泌物之一,是反映肾脏器官发生病理变化的窗口。尿常规作为尿液传统检查方法,具有下列缺点:操作烦琐,耗时费力,重复性差,不易定量,缺乏标准化。随着科学技术的快速发展,尿液分析已经进入尿颗... 1尿沉渣检验的临床价值尿液是机体内的重要排泌物之一,是反映肾脏器官发生病理变化的窗口。尿常规作为尿液传统检查方法,具有下列缺点:操作烦琐,耗时费力,重复性差,不易定量,缺乏标准化。随着科学技术的快速发展,尿液分析已经进入尿颗粒分析时代[1]。尿沉渣检查为患者的临床医疗与诊断提供了十分关键的临床数据[2]特别对肾脏疾病的诊断治疗具有重要作用, 展开更多
关键词 un-500 全自动尿沉渣分析仪 故障:分析处理
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浅谈un-、in-、dis-三个英语否定前缀
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作者 郭卫华 田咏俐 《石家庄理工职业学院学术研究》 2012年第Z1期9-10,23,共3页
英语否定前缀在英语派生词缀中占有重要地位,对它们的熟练掌握能够使英语学习者更加高效、精确地学习和积累英语词汇。本文简要分析了英语中最常见的un-、in-、dis-三个否定前缀的构词特点和语义特征,以期能够对英语学习者的词缀学习和... 英语否定前缀在英语派生词缀中占有重要地位,对它们的熟练掌握能够使英语学习者更加高效、精确地学习和积累英语词汇。本文简要分析了英语中最常见的un-、in-、dis-三个否定前缀的构词特点和语义特征,以期能够对英语学习者的词缀学习和词汇积累起到一定的指导作用。 展开更多
关键词 un- in- dis- 否定前缀
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固化、占位和动词语义在un-[VERB]构式发展中的作用研究 被引量:1
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作者 赵宝山 张晓鹏 《解放军外国语学院学报》 CSSCI 北大核心 2023年第4期119-127,F0003,共10页
本研究考察了固化、占位和动词语义在中国英语学习者un-[VERB]构式发展中的作用。受试为大学二年级、四年级的学生和英语教师。他们根据提示判断是否将un-动词和非un-动词用于un-[VERB]构式,描述目标图片。结果显示:受试使用un-动词描... 本研究考察了固化、占位和动词语义在中国英语学习者un-[VERB]构式发展中的作用。受试为大学二年级、四年级的学生和英语教师。他们根据提示判断是否将un-动词和非un-动词用于un-[VERB]构式,描述目标图片。结果显示:受试使用un-动词描述图片的频次随着英语水平的提高而增加,四年级学生使用非un-动词描述图片的频次高于二年级学生和教师。动词使用频次是影响二年级学生将动词用于un-[VERB]构式的主要因子,un-[VERB]的同义构式和动词语义是影响四年级学生和教师将动词用于un-[VERB]构式的主要因子。结果支持固化、占位和语义聚类假设。 展开更多
关键词 un-[VERB]构式 固化 占位 动词语义 语义聚类 中国英语学习者
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UN-U_(3)Si_(2)复合燃料的多尺度蠕变行为研究
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作者 杨青峰 谢哲骁 +8 位作者 陈平 张静 高士鑫 丁国琛 周毅 尹春雨 丁淑蓉 何梁 孙丹 《核技术》 CAS CSCD 北大核心 2022年第12期57-64,共8页
UN-U_(3)Si_(2)复合燃料在未来先进耐事故燃料元件中具有良好的发展前景,其堆内运行所产生的辐照蠕变及热蠕变对元件的辐照热力耦合行为及安全性会产生重要影响。基于文献中的宏观蠕变实验结果,分别针对UN和U_(3)Si_(2)多晶燃料主控的... UN-U_(3)Si_(2)复合燃料在未来先进耐事故燃料元件中具有良好的发展前景,其堆内运行所产生的辐照蠕变及热蠕变对元件的辐照热力耦合行为及安全性会产生重要影响。基于文献中的宏观蠕变实验结果,分别针对UN和U_(3)Si_(2)多晶燃料主控的蠕变机制进行分析,通过拟合得到考虑空位扩散和位错运动机制的蠕变率模型,该模型的预测结果与实验结果吻合很好,证明了模型的合理性;基于均匀化理论建立了去除辐照肿胀效应后UN-U_(3)Si_(2)复合燃料宏观蠕变与各组分贡献的关联模型。基于文献上的复合燃料金相结构图,发展了随机建模方法,对UN-U_(3)Si_(2)复合燃料(20%U_(3)Si_(2))辐照条件下单轴拉伸蠕变实验进行了数值模拟,获得了组分材料对复合燃料宏观等效蠕变所产生的贡献,并分析了蠕变机制。分析结果表明:UN和U_(3)Si_(2)存在的辐照肿胀差异,导致复合燃料内部产生了强烈的力学相互作用;在裂变密度达到4.32×10^(27)fissions·m^(−3)时,颗粒与基体相界面处的最大von Mises应力约为外部施加的均布拉力的6倍,但由于存在低应力区,两种材料的辐照肿胀对复合燃料宏观等效蠕变应变的影响可以忽略不计。 展开更多
关键词 un-U_(3)Si_(2) 蠕变机制 辐照肿胀 均匀化理论 宏观等效蠕变
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中国EFL学习者的派生限制习得研究——以动词前缀un-为例
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作者 韩百敬 曾涛 《外语学刊》 CSSCI 北大核心 2019年第4期86-90,共5页
本文以动词前缀un-为例,通过语法判断和跨通道启动诱导产出任务考察中国EFL学习者的派生限制习得情况和语义限制、前摄、固着3个因素的作用。研究表明:综合习得与语言水平正相关,但合格产出呈U型趋势,反映出派生产出自动化进程的缓慢与... 本文以动词前缀un-为例,通过语法判断和跨通道启动诱导产出任务考察中国EFL学习者的派生限制习得情况和语义限制、前摄、固着3个因素的作用。研究表明:综合习得与语言水平正相关,但合格产出呈U型趋势,反映出派生产出自动化进程的缓慢与滞后。派生词的判断和产出总体上与语义限制正相关,与固着和前摄负相关;语义限制效应相对普遍、持久,而前摄、固着效应复杂多变。3因素的协同互补机制及其作用强度、范围、动态变化和交互情况可在FIT框架内得到有效阐释。 展开更多
关键词 派生限制习得 un- 语义限制 前摄 固着
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Design of Diode Type Un-Cooled Infrared Focal Plane Array Readout Circuit 被引量:3
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作者 Li-Nan Li Chuan-Qi Wue 《Journal of Electronic Science and Technology》 CAS 2012年第4期309-313,共5页
The diode infrared focal plane array uses the silicon diodes as a sensitive device for infrared signal measurement. By the infrared radiation, the infrared focal plane can produces small voltage signals. For the tradi... The diode infrared focal plane array uses the silicon diodes as a sensitive device for infrared signal measurement. By the infrared radiation, the infrared focal plane can produces small voltage signals. For the traditional readout circuit structures are designed to process current signals, they cannot be applied to it. In this paper, a new readout circuit for the diode un-cooled infrared focal plane array is developed. The principle of detector array signal readout and small signal amplification is given in detail. The readout circuit is designed and simulated by using the Central Semiconductor Manufacturing Corporation (CSMC) 0.5 μm complementary metal-oxide-semiconductor transistor (CMOS) technology library. Cadence Spectre simulation results show that the scheme can be applied to the CMOS readout integrated circuit (ROIC) with a larger array, such as 320×240 size array. 展开更多
关键词 Capacitor trans-impedance amplifier detector array signal diode un-cooled infrared focalplane arrays readout circuit small signal amplification.
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基于UN-150ZB移动式钢轨闪光焊机的自诊断系统
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作者 赵红光 何超 吕其兵 《现代焊接》 2012年第6期29-31,共3页
本文针对UN5—150ZB钢轨闪光焊焊机在现场使用中出现故障而诊断检测困难的问题,论文提出了一种基于计算机和可编程控制器通讯实现焊机故障检测的自诊断系统。故障诊断时通过通讯将钢轨闪光焊机的开关量输入信息、模拟量输入信息、PLC... 本文针对UN5—150ZB钢轨闪光焊焊机在现场使用中出现故障而诊断检测困难的问题,论文提出了一种基于计算机和可编程控制器通讯实现焊机故障检测的自诊断系统。故障诊断时通过通讯将钢轨闪光焊机的开关量输入信息、模拟量输入信息、PLC的所有输出点信息等各种状态数据读入到计算机,计算机的软件自动进行判断,并将判断结果以文字或图形形式输出,指示故障类型和位置,为设备维修和故障处理提供指导,从而维修人员可以快速处理设备故障,提高焊接生产效率。 展开更多
关键词 un-150ZB PLC 上位机 诊断系统
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Research advances of un-symmetric constitutive theory of anisotropic viscoelastic liquids and its hydrodynamic behavior 被引量:1
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作者 韩式方 《Journal of Central South University》 SCIE EI CAS 2008年第S1期1-4,共4页
Research advances of un-symmetric constitutive equation of anisotropic fluid,influence of un-symmetric stress tensor on material functions,vibrational shear flow of the fluid with small amplitudes and rheology of anis... Research advances of un-symmetric constitutive equation of anisotropic fluid,influence of un-symmetric stress tensor on material functions,vibrational shear flow of the fluid with small amplitudes and rheology of anisotropic suspension were reported.A new concept of simple anisotropic fluid was introduced.On the basis of anisotropic principle,the simple fluid stress behaviour was described by velocity gradient tensor F and spin tensor W instead of velocity gradient tensor D in the classic Leslie-Ericksen continuum theory.Two relaxation times analyzing rheological nature of the fluid and using tensor analysis a general form of the constitutive equation of co-rotational type was introduced.More general model LCP-H for the fluid was developed.The unsymmetry of the shear stress was predicted by the present continuum theory for anisotropic viscoelastic fluid-LC polymer liquids.The influence of the relaxation times on material functions was specially studied.It is important to study the unsteady vibrational rotating flow with small amplitudes,as it is a best way to obtain knowledge of elasticity of the LC polymer,i.e.dynamic viscoelasticity.For the shear-unsymmetric stresses,two shear stresses were obtained thus two complex viscosities and two complex shear modulus(i.e.first and second one) were introduced by the constitutive equation which was defined by rotating shear rate introduced by author.For the two stability problems of fluid,such as stability of hydrodynamic flow and orientational motion,were discussed.The results show that the polymer suspension systems exhibit anisotropic character.The PNC systems can exhibit significant shear-thinning effects.For more concentrated polymer nano-suspensions,the first normal stress difference change from positive to negative,which is similar to LC polymer behavior. 展开更多
关键词 un-symmetric constitutive equation ANISOTROPIC fluid liquid crystalline POLYMER stability hydrodynamic FLOW orientational motion vibrational shear FLOW rheology of POLYMER suspension
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Survey on Pre-pregnancy Health Knowledge and Service Demands among Un-pregnant Married Women
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作者 Yu-hua LI Hong LIANG +9 位作者 Li-feng ZHOU Ren-li WANB Er-sheng GAO Wen-ping SHEN Yue DONG Zhi-hui GU Rui-zhu CHEN Wei-jue CAO Guo-liang ZHOU Xiao-ping ZHOU 《Journal of Reproduction and Contraception》 CAS 2006年第3期195-200,共6页
Objective To understand the pre-pregnancy health knowledge and service needs among un-pregnant married women in Shanghai. Methods A total of 968 newly-married un-pregnant women in Changqiao, Lingyun sub-districts and ... Objective To understand the pre-pregnancy health knowledge and service needs among un-pregnant married women in Shanghai. Methods A total of 968 newly-married un-pregnant women in Changqiao, Lingyun sub-districts and Huajing town of Xuhui district, Shanghai, were recruited and interviewed by structured questionnaire to collect the information on pre-pregnancy health knowledge and service demands. Results 1) Newly-married women thought the contraceptive methods suitable for them was male condom(84.4%), followed by oral contraceptives(54%), emergent contraceptive(52.5%) and contraceptive suppository (48.3%). 2) The score of pre-pregnancy health knowledge was 54.7±14.5 among the subjects. The participants with junior college or a bachelor had more knowledge than those with junior or senior high school, and those who were engaged in medicine /education/science field had higher score. 3) They had higher knowing rate on the common knowledge, and the rate was above 80%. But the knowing rate on the knowledge of birth defect was low, and all below 50%. 4)A proportion of 52. 7% of the respondents knew that there was a station for reproductive health service in their communities, but only 45.5% received the service from the station, 87.0% thought they had insufficient or scarce knowledge, 73.6% planned to consult before pregnancy training courses on preparing pregnancy. and 63.6% were willing to attend the Conclusion The participants had certain pre-pregnancy health knowledge, but still need being improved," in addition, they had higher needs on knowledge and service of birth defect prevention, at the same time they can't make full use of the existing reproductive health institution. 展开更多
关键词 un-pregnant women pre-pregnancy health knowledge service use demand
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Mineralogical Characterization of Sieved and Un-Sieved Samples
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作者 Rolando Lastra William Petruk 《Journal of Minerals and Materials Characterization and Engineering》 2014年第1期40-48,共9页
Mineralogical characterization applied to mineral processing is now widespread. The first step for a mineralogi- cal characterization study is usually size fractionation. Preparation of polished sections is done on si... Mineralogical characterization applied to mineral processing is now widespread. The first step for a mineralogi- cal characterization study is usually size fractionation. Preparation of polished sections is done on size fractions to reduce complications in making representative cross sections of particles with large size differences. A sample is commonly fractionated into five or six size intervals. The drawback of this procedure is that it makes liberation studies more expensive, because one sample actually produces five or six sub-samples that need to be studied, i.e. one from each size interval. Thus to reduce cost of liberation studies, it would be desirable to study the un-sized sample. This paper provides a comparative liberation study of a set of samples both using size fractions and using the un-sized samples. The samples studied are the feed, the concentrate and the tails of a lead rougher flotation circuit. The results consistently show significant differences between the sized and the un-sized samples. Nevertheless, the results indicate that un-corrected liberation data from un-sized samples can be used for comparative studies that involve several related samples. Thus, it is possible to improve (or further understand) a concentrator circuit by using mineralogical data from un-sized samples around such circuit. 展开更多
关键词 MINERAL LIBERATION Sieved un-Sieved
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Contrastive analysis of prefix dis- and un- in English
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作者 李集团 《International English Education Research》 2014年第5期89-91,共3页
English prefix dis- and tin- are commonly surveyed along with some other negative prefixes. However, there are many cases in which prefix dis- and un- can be attached to the same root, causing the difficulty in distin... English prefix dis- and tin- are commonly surveyed along with some other negative prefixes. However, there are many cases in which prefix dis- and un- can be attached to the same root, causing the difficulty in distinguishing the comprehension of the two prefixes' semantic roles. Considering this issue, this paper endeavors to clarify the respective morphological processes and explain their specific semantic roles. 展开更多
关键词 dis- un- morphological process semantic role
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Comparison of Seam Strength between Dyed and Un-Dyed Gabardine Apparels: A Research on Lapped &Superimposed Seam
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作者 Kaniz Farhana Md. Syduzzaman Dilruba Yeasmin 《Journal of Textile Science and Technology》 2015年第2期75-84,共10页
Today is the golden age of fashion. Fashion garments and apparels have been used everywhere to cope with the fashion era. These fashion garments and apparels are made of the fabrics of various structures and component... Today is the golden age of fashion. Fashion garments and apparels have been used everywhere to cope with the fashion era. These fashion garments and apparels are made of the fabrics of various structures and components through various processes. Among them gabardine is one of the most remarkable type of fabric and apparel dyeing is the latest process used for fashion apparel. From this research, the seam strength variations between dyed and un-dyed gabardine apparels after conceding the garment dyeing process can be known. It is a comparative research work which will deliver very effective knowledge about various types of seam, seam strength and seam performance. For comparative study, many dummy apparels body have been produced as samples which are dyed in Hams washing and dyeing limited. After that all samples have tested in Thermax woven dyeing laboratory. Since Bangladesh is a very potential fashion market and the fashion garments are being manufactured more and more. Hence the fashion trend is rapidly going to garments dyeing from conventional fabric/yarn dyeing processes. Gradually garments dyeing order are increasing higher to higher. 展开更多
关键词 SEAM SEAM Strength GABARDINE APPAREL Dyed APPAREL un-Dyed APPAREL APPAREL DYEING
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Improved Adaptive Differential Evolution Algorithm for the Un-Capacitated Facility Location Problem
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作者 Nan Jiang Huizhen Zhang 《Open Journal of Applied Sciences》 CAS 2023年第5期685-695,共11页
The differential evolution algorithm is an evolutionary algorithm for global optimization and the un-capacitated facility location problem (UFL) is one of the classic NP-Hard problems. In this paper, combined with the... The differential evolution algorithm is an evolutionary algorithm for global optimization and the un-capacitated facility location problem (UFL) is one of the classic NP-Hard problems. In this paper, combined with the specific characteristics of the UFL problem, we introduce the activation function to the algorithm for solving UFL problem and name it improved adaptive differential evolution algorithm (IADEA). Next, to improve the efficiency of the algorithm and to alleviate the problem of being stuck in a local optimum, an adaptive operator was added. To test the improvement of our algorithm, we compare the IADEA with the basic differential evolution algorithm by solving typical instances of UFL problem respectively. Moreover, to compare with other heuristic algorithm, we use the hybrid ant colony algorithm to solve the same instances. The computational results show that IADEA improves the performance of the basic DE and it outperforms the hybrid ant colony algorithm. 展开更多
关键词 un-Capacitated Facility Location Problem Differential Evolution Algorithm Adaptive Operator
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高燃耗下UN-FeCrAl燃料元件稳态及瞬态热力学性能分析
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作者 何梁 秋博文 +7 位作者 邬周志 张坤 陈平 高士鑫 胡超 邢硕 范航 王严培 《核动力工程》 EI CAS CSCD 北大核心 2022年第6期227-231,共5页
UN-FeCrAl燃料元件作为耐事故燃料高燃耗应用的主要方案之一,需要评价其在高燃耗下的热力学性能。本研究基于FUPAC软件对UN-FeCrAl燃料元件在燃耗68000 MW·d·t^(-1)(U)下的稳态和瞬态热力学性能进行了预测。分析结果表明,稳... UN-FeCrAl燃料元件作为耐事故燃料高燃耗应用的主要方案之一,需要评价其在高燃耗下的热力学性能。本研究基于FUPAC软件对UN-FeCrAl燃料元件在燃耗68000 MW·d·t^(-1)(U)下的稳态和瞬态热力学性能进行了预测。分析结果表明,稳态工况下UN-FeCrAl燃料元件热力学性能表现良好;瞬态下UN燃料的芯块中心温度最高仅为862℃,可满足芯块温度设计要求,但FeCrAl包壳的瞬态应力最大将达到459 MPa,且瞬态应变量相比于稳态应变量最大增加了0.23%,这可能会使FeCrAl包壳面临瞬态应力和瞬态应变准则超限的风险。因此后续研究应重点关注FeCrAl包壳的瞬态应力和瞬态应变性能。 展开更多
关键词 耐事故燃料 UN燃料 FeCrAl包壳 热力学性能
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高预充压对UN-FeCrAl燃料棒性能影响分析
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作者 何梁 张坤 +3 位作者 陈平 高士鑫 尹春雨 胡超 《科学技术创新》 2023年第17期18-22,共5页
本文采用FUPAC对高预充压设计下的UN-FeCrAl燃料棒在高燃耗下的性能进行了分析。分析结果表明,高预充压设计下可有效增大芯块-包壳间隙闭合时间,在稳态工况下可避免芯块-包壳发生接触,降低包壳发生PCI破损的风险,同时将导致燃料棒内压... 本文采用FUPAC对高预充压设计下的UN-FeCrAl燃料棒在高燃耗下的性能进行了分析。分析结果表明,高预充压设计下可有效增大芯块-包壳间隙闭合时间,在稳态工况下可避免芯块-包壳发生接触,降低包壳发生PCI破损的风险,同时将导致燃料棒内压相对较大,但得益于UN燃料芯块燃料温度较低的优点,其寿期末的燃料棒内压仍低于冷却剂压力,可满足燃料棒内压设计要求;此外,高预充压设计对燃料温度、裂变气体释放率的影响较小,并有利于降低包壳Mises应力和应变。 展开更多
关键词 耐事故燃料 UN燃料 FeCrAl包壳 高预充压
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从瑞士雅典表2025年新款Blast陀飞轮 谈钟表专利创新的创造、保护和利用 被引量:1
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作者 王雷 《钟表》 2025年第4期100-101,共2页
2025年7月,瑞士Ulysse Nardin雅典表推出了BLAST的陀飞轮腕表,这块腕表盘脸设计非常漂亮让人眼前一亮,八枚齿轮与飞行陀飞轮在表盘正面凌空悬浮。机心仍为UN-176,结构与2018年首发的Executive/Blast Free Wheel相同,主要变化在材质与视... 2025年7月,瑞士Ulysse Nardin雅典表推出了BLAST的陀飞轮腕表,这块腕表盘脸设计非常漂亮让人眼前一亮,八枚齿轮与飞行陀飞轮在表盘正面凌空悬浮。机心仍为UN-176,结构与2018年首发的Executive/Blast Free Wheel相同,主要变化在材质与视觉呈现。 展开更多
关键词 专利创新 机心 雅典表 陀飞轮腕表 BLAST un-176
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联合国世界水发展报告述评 被引量:2
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作者 胡庆芳 张根瑞 +3 位作者 方琼 邱豆豆 周天涛 苏鑫 《水利水运工程学报》 北大核心 2025年第3期1-13,共13页
联合国世界水发展报告(WorldWaterDevelopmentReport,WWDR)是全球水资源评估计划的重要组成部分之一,为决策者提供了制定和实施可持续水资源政策的知识、工具和案例。简述了WWDR的历史沿革,对2003年以来历次报告作了总结评述,同时重点... 联合国世界水发展报告(WorldWaterDevelopmentReport,WWDR)是全球水资源评估计划的重要组成部分之一,为决策者提供了制定和实施可持续水资源政策的知识、工具和案例。简述了WWDR的历史沿革,对2003年以来历次报告作了总结评述,同时重点介绍了2024年WWDR的主要内容。最后结合历届WWDR所提出的重要观点、解决水问题的对策和中国水安全保障实际情况,阐述了若干思考和认识。 展开更多
关键词 水危机 可持续发展 联合国水机制 世界水发展报告 水与和平及繁荣
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