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二级校准用温度固定点

上海计量测试 2002年第1期29卷 15-19页

作者： Li,z.,Hirst m.,zhao Hart Scientific

近年来出现了一种新的温度固定点校准技术。这种新技术不同于经典的固定点技术，所用设备简单，操作方便，工作效率高，主要适用于二级和工业温度计的校准。本文简要介绍了若干应用例子：一种不需用液氮或干冻冻制及杜瓦瓶保存的复现水... 详细信息

近年来出现了一种新的温度固定点校准技术。这种新技术不同于经典的固定点技术，所用设备简单，操作方便，工作效率高，主要适用于二级和工业温度计的校准。本文简要介绍了若干应用例子：一种不需用液氮或干冻冻制及杜瓦瓶保存的复现水三相点的新方法，自动金属固定点装置和不锈饮固定点容器及其复现装置等。

关键词：二级校准温度固定点温度校准计量学温度计量温度计

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微电子的挑战和瑞士立达纺机厂的回答

国外纺织技术(纺织分册) 1986年第11期 43-46页

作者： m.zünd 蔡绍泉

在纺织机械的发展中,现在已经朝着全自动流程的阶段发展,机器控制系统之间的信息交流,促使了机器性能优化,提高效率以及改善质量。除了机器上电器的主要用途外——诸如

关键词：纺机微电子气流纺纱机转杯纺纱机纺纱机械机器控制纺纱厂微机系统计算机系统电器电气设备可编程控制器程序控制器数据处理系统

morphologic,Radiographic,and Stereomicroscopic Evaluation of Teeth Subjected to High Temperatures:An In vitro Forensic Study

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Journal of Forensic Science and medicine 2023年第3期9卷 228-235页

作者： m.Sai Geethika N.Purnachandra Rao Naik A.Ravi Kiran y.Samatha B.Naveen Kumar P.Shruthi Sethu manjusha Saranu K.Pavani Sanjana marpuri Department of Oral medicine and Radiology Sibar Institute of Dental SciencesGunturAndhra PradeshIndia

Background:To evaluate morphologic,radiographic,and stereomicroscopic changes of teeth when subjected to specific high temperatures in both direct heat and gradual heat and to compare the changes among two heat groups and also among different types of *** and methods:An in vitro study was conducted on 90 healthy extracted human teeth,in which the teeth were divided into two *** 1(45)was subjected to direct heat and Group 2(45)was subjected to gradual *** 1 and Group 2 were further subdivided into three subgroups(A)anteriors,(B)premolars,and(C)molars each consisting of 15 *** were subjected to temperatures of 200°C,400°C,600°C,800°C,and 1000°C in a muffle electric *** color changes were noted using the Revised munsell soil color chart and the radiographic and stereomicroscopic changes were *** results obtained were subjected to statistical ***:Teeth in direct heat showed more destructive changes at lower temperatures,i.e.,400°C and 600°C when compared to gradual heat where changes are observed at 600°C and 800°*** different types of teeth,anteriors and premolars showed more changes when compared to *** and Conclusion:It can be concluded that dental evidence may provide clues to solve the mystery in fire investigations as dental structures are the last to be destroyed under extreme conditions,whether temperature,acid,or putrefaction.

关键词： Color changes in teeth forensic odontology high temperatures incinerated teeth radiographs stereomicroscope

形变双奇核^(186)Au的高自旋态能级结构

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中国科学：物理学、力学、天文学 2012年第10期42卷 1062-1075页

作者：李仕成张玉虎周小红石跃柳敏良方永得王建国高丙水许甫荣 OSHImA m TOH y KOIzUmI m OSA A KImURA A HATSUKAWA y HAyAKAWA H SHIzUmA T KATAKURA J mATSUDA m mORIKAWA T SUGAWARA m KUSAKARI H 中国科学院近代物理研究所兰州730000 中国科学院研究生院北京100049 北京大学物理学院核物理与核技术国家重点实验室北京100871 Japan Atomic Energy Agency Tokai-MuraIbaraki 319-1195Japan Department of Physics Kyushu UniversityFukuoka 812-81Japan Chiba Institute of Technology NarashinoChiba 275-0023Japan Chiba University Inage-kuChiba 263-8512Japan

利用重离融合蒸发反应和在束γ谱学验方法,研究了双奇核186Au的高旋态能级结构.扩展了186Au核基于πh9/2i13/2和πi13/2i13/22-准粒组态的转动带能级纲图,并重新指认了两条转动带的能级旋值,发现两条转动带在低旋区均出现旋称反转.... 详细信息

利用重离融合蒸发反应和在束γ谱学验方法,研究了双奇核186Au的高旋态能级结构.扩展了186Au核基于πh9/2i13/2和πi13/2i13/22-准粒组态的转动带能级纲图,并重新指认了两条转动带的能级旋值,发现两条转动带在低旋区均出现旋称反转.系统地分析了Au同位素双奇核πh9/2i13/2,πi13/2i1/3和πh-111/2-νi-1312转动带的旋称劈裂特征.本工对186Au核πh-111/-2νi-132/2j(j=p3/2,f5/2)转动带(17+)态之上能级结构了修改.根据验提取的准粒顺排角动量以及对Au双奇核带结构的系统性比较和分析,别出了一条组态为πh-111/-2νi-1322h-19/2的扁椭球转动带.

关键词：高旋态能级间隔系统性旋称反转准粒顺排

KINETICS OF REDUCTION IRON OXIDE IN CaO-SiO_2-Al_2O_3-Fe_tO SLAGS WITH CARBON SATURATED IN mOLTEN IRON

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Acta metallurgica Sinica(English Letters) 1997年第6期10卷 515-522页

作者： X.m. yang D.B. Huang L. T. Kong T.J. yang y.S. Xie and D. G. Wang(Institute of Chemical metallurgy, Chinese Academy of Sciences, Beijing 100080, China)(University of Science and Technology Beijing, Beijing 100083, China) Inst of Chemical metallurgy Chinese Acad of Sciences Beijing China

The rate of reducing Fet O in CaO-SiO2-Al2O3-Fet O slags with carbon saturated in molten iron has been determined in a graphite crucible in the temperature range of 1673-1773K. The effects of temperature, slag basicity and FetO content on the reduction rate have also been discussed. Test results show that the reduction rate increases with increasing temperature or FEtO concentration in slags, and the reduction rate has a parabolic relation with the simple basicity or optical basicity of slag, the maximum reduction rate being observed at around CaO/SiO2=1.5 of molten slags. The reduction reaction order is 1. 73 or 1.80, and the reduction activation energy is 299.9 or 295.9 kJ/mol in regard to Fet O weight content or Fet O activity calculated by using regular solution model, respectively. The reduction rate of CaO-SiO2-Al2 O3-Fet O slags with carbon saturated in molten iron is in the range of 0.32-3.48 mol-O/cm2·s.

关键词： CaO-SiO_2-Al_2O_3-Fe_tO slags reduction kinetics molten iron,Fe_tO activity

US-Russian Civilian Research and Development Fund Project： An origin of microdiamonds in metamorphic rocks of the Kokchetav massif, Northern Kazakhstan

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Episodes 2003年第4期26卷 290-294页

作者： N.V.Sobolevt V.S.Shatsky J.G.Liou R.y.zhang S.L.Hwang P.Shen H.T.Chu T.F.yui A.A.zayachkovsky m.A.Kasymov UnitedInstituteofGeology GeophysicsandMineralogySiberianBranchofRussianAcademyofScienceNovosibirsk630090Russia DepartmentofGeologicalandEnvironmentalSciences StanfordUniversityStanfordCA94305USA DepartmentofmaterialsScienceandEngineering NationalDongHwaUniversityHualienTaiwanChina InstituteofmaterialsScienceandEngineering NationalSunYat-senUniversityKaohsiungTaiwanChina CentralGeologicalSurvey P.O.Box968TaipeiTaiwanChina InstituteofEarthSciences AcademiaSinicaTaipeiTaiwanChina NEDRAGeologicalExpedition 475013KokchetavKazakhstan InstituteofGeologicalSciences AcademyofSciencesoftheRepublicofKazakhstanAlmaty480100Kazakhstan

The Kokchetav massif of northern Kazakhstan is a typelocality of occurrence of microdiamonds in ultrahighpressure metamorphic" rocks. It records continental subduction and exhumation from depths greater than 120 km and provides unparalleled insights into mantle dynamics, global material recycling and the processes responsible for the genesis and destruction of continent. Through the support of a US Civilian Development and Research Fund, a group of Russian, US, Taiwan Residents and Kazakhstan geologists visited the reconstructed 800-m underground gallery to conduct field survey and sample collections. This gallery provides a useful geologic laboratory for international community to undertake similar geotectonic or different ecological and environmental studies.

关键词：变质岩地质调查动力学俄罗斯美国

Effect of restorative techniques on fracture resistance of endodontically treated premolars

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Open Journal of Stomatology 2013年第7期3卷 379-385页

作者： Bandar m. A. Al-makramani Abdul A. A. Razak Ng m. yi Sin y. ying Fuad A. Al-Sanabani Dental Student Faculty of Dentistry University of Malaya Kuala Lumpur Malaysia Department of Conservative Dentistry Faculty of Dentistry Sana’a University Sana’a Yemen Department of Conservative Dentistry Faculty of Dentistry University of Malaya Kuala Lumpur Malaysia Department of Prosthodontics Faculty of Dentistry Sana’a University Sana’a Yemen

Purpose: This study was aimed to evaluate the effect of restorative materials and glass fiber post on the fracture resistance of endodontically treated premolars. material and methods: Fifty extracted single rooted lower premolars were used in this in vitro study and divided into 5 groups: sound teeth (control group);mesial-occlusal-distal (mOD) preparation + endodontic treatment + composite restoration;mOD preparation + endodontic treatment + glass fiber post + composite restoration;mOD preparation + endodontic treatment + amalgam restoration;mOD preparation + endodontic treatment + glass fiber post + amalgam restoration. The specimens were loaded on a universal testing machine at the crosshead speed of1 mm/min until fracture. The data were analyzed using two-way ANOVA test. Results: The mean loads at fracture were 860.11 N, 801.79 N, 761.39 N, 737.14 N and 707.85 N respectively. There were no statistically significant differences (P > 0.05) in the fracture resistance of teeth restored with composite and amalgam, as well as restored with or without glass fiber post. Conclusions: The type of restorative material and the usage of glass fiber post do not have visible influence on the fracture resistance of the endodontically treated mandibular premolars.

关键词： Endodontic Treatment Fiber Post Fracture Resistance

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虚拟水贸易在我国粮食安全问题中的应用

水科学进展 2006年第1期17卷 102-107页

作者：马静汪党献 A. y. Hoekstra 夏海霞中国水利水电科学研究院水资源研究所北京100044 UNESCO-IHE Institute for Water Education 2601 DA Delft The Netherlands 中国水利报社北京100053

借助虚拟水的概念，分析以粮食为载体的虚拟水国际、区际流量关系，以勾勒我国虚拟水贸易的基本格局。通过对未来我国在不同粮食发展战略下的粮食供需情况，确定我国粮食进口基本规模，对未来我国虚拟水贸易格局进行展望。分析结果表明... 详细信息

借助虚拟水的概念，分析以粮食为载体的虚拟水国际、区际流量关系，以勾勒我国虚拟水贸易的基本格局。通过对未来我国在不同粮食发展战略下的粮食供需情况，确定我国粮食进口基本规模，对未来我国虚拟水贸易格局进行展望。分析结果表明，1999年我国北方通过粮食贸易向南方地区输出的虚拟水量达到184亿m^3。我国北方地区以有限的水资源在支持其他区域发展、确保国家粮食安全方面发挥了不可替代的作用。未来30年中国将面临新增粮食需求1．4亿～2．0亿t的巨大压力，在保持较高自给水平的前提下，我国虚拟水贸易的格局不会发生重大变化。外流域调水工程是保障国家粮食安全，维护社会稳定，促进可持续发展和造福中国人民的重大举措。虚拟水战略可作为跨流域调水的补充，在保障缺水地区水安全方面发挥重要作用。

关键词：虚拟水粮食安全区域贸易

Choroidal thickness measurements in young Saudi adult population: a cross-sectional study

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International Journal of Ophthalmology(English edition) 2023年第11期16卷 1814-1819页

作者： mohammed m Althomali Ahmed A Alharbi Nouf m Albnayan Abdulaziz m Alkhudhair muteb K Alanazi Optometry Department College of Applied Medical SciencesKing Saud UniversityRiyadh 11362Saudi Arabia

AIm:To determine the choroidal thickness(CT)in young healthy Saudi adults using spectral-domain optical coherence tomography(SD-OCT)with an automated CT segmentation ***:Fifty-eight young adults(total of 116 eyes),39 males and 19 females participated in this study between the ages of 18 and 38y(mean 22.65±3.9y).All participants underwent ophthalmic screening examination,including the SD-OCT for measurements of CT in each quadrant egmented into five eccentric regions starting from the foveal region up to 4.5 mm towards the ***:The choroid was thickest in the foveal region(central 1 mm,300±60μm)and began to progressively thinner beyond the parafovea(1.5–2.5 mm,284±67μm)towards the peripheral region(3.5–4.5 mm from the fovea,254±83μm).The superior choroid showed the thickest profile(309±57μm),while the nasal choroid exhibited the thinnest(229±76μm).The rate of the thinning with increasing eccentricity was more predominant in the nasal choroid,which thinned from the foveal region(294±58μm)to the peripheral region(158±55μm).The superior and inferior choroid did not show a statistically significant thinning with eccentricity(all P>0.05).There was no statistically significant difference in the CT between gender,age,and laterality of the eyes(all P>0.05).A significant association of myopia with thinner subfoveal choroid was observed(Pearson’s,r=0.37),and regression analysis showed that a 10.3μm choroidal thinning for each diopter increase of ***:CT profile depends on eccentric and the *** CT profile across the measured area in the young Saudi adult population is comparable to other previous *** error is critical for CT evaluation.

关键词： choroidal thickness optical coherence tomography young adults Saudi population