检索结果-南通市图书馆

Properties and applications of cold supersonic gas jet

在线全文

学校读者我要写书评

暂无评论

Science China(physics,Mechanics & Astronomy) 2006年第6期49卷 709-715页

作者： ZHANG Shaofeng1,2.MA Xinwen1,2.LIU Huiping2.LI Bin1,2.& ZHU Xiaolong1,2.1. institute of modern physics,chinese {2. of sciences,lanzhou 730000,China 2. Graduate University of chinese academy of sciences,Beijing 100049,China 1. institute of modern physics Chinese Academy of Sciences Lanzhou 730000 China 2. Graduate University of chinese academy of sciences Beijing 100049 China

By analyzing the formation mechanism of a supersonic gas jet,a set of equations which describe the atomic beam properties were established. The influence of initial temperature,initial pressure,background gas pressure and pumping speed was discussed in detail. A simulation program was developed based on the equations,and the results under different initial conditions were obtained. The results are in good agreement with the experimental data,and suggest that,in order to get much smaller transverse momentum in collision experiments,it is necessary to lower the initial temperature and the initial pressure of the supersonic gas jet,together with increasing the pumping speed. These results are very instructive for construction of a new generation of cold supersonic gas jets.

关键词： cold supersonic gas jet,zone of silence,nozzle,skimmer.

Study on the Reaction of Proteins with 5-Nitrosalicylfluorone-molybdenum(Ⅵ) Complex by Spectrophotometry in PVA 12. Microemulsion

在线全文

学校读者我要写书评

暂无评论

chinese Journal of Chemistry 2004年第7期22卷 714-718,615页

作者：魏琴吴丹杜斌张慧欧庆瑜lanzhou institute of Chemical {2. chinese academy of sciences lanzhou Gansu 730000 China School of Chemistry & Chemical Engineering Jinan University Jinan Shandong 250022 China Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou Gansu 730000 China School of Chemistry & Chemical Engineering Jinan University Jinan Shandong 250022 China

The application of 5'-nitrosalicylfluorone (5'-NSF)-molybdenum(VI) complex as a spectroscopic probe was studied. In the buffer medium of HOAc-NaOAc at 3.45 and in the presence of PVA 12. microemulsion, 5'-NSF-Mo(VI) complex combines protein rapidly to form a stable compound, leading to an absorbance decrease at 52. nm of 5'-NSF-Mo(VI) complex. According to this change, microdetermination of protein has been described. Bovine serum albumin (BSA) could be determined in the linear range of 0—16 g昺L-1 with the detection limit of 11 ngmL-1. Many amino acid and metal ions studied do not interfere with the assay. The method possesses high sensitivity as well as high selectivity. It can be used to determine protein in human urine and milk powder successfully. The relative standard deviations are in all instances less than 4.7%, and the recoveries are between 97.6% and 106.0%. Moreover, the binding number of BSA with the complex, which is determined by using molar ratio, Rosenthanl graphic and slope ratio methods, is in good agreement with each other.

关键词： protein spectrophotometry 5'-NSF-Mo(VI) complex microemulsion

Characterization and Tribological Behavior of Octadecene,Dodecene and Undecenoic Acid Films on Si Substrate

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2005年第5期21卷 671-674页

作者： Jinfang ZHOU+ and Shengrong YANGState Key Laboratory of Solid Lubrication, lanzhou institute of Chemical {2., chinese academy of sciences, lanzhou730000, China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 China

The films of octadecene, dodecene, and undecenoic acid were prepared on H-terminated Si surface in the presence of ultraviolet irradiation. The resulted films were characterized with water-contact angle measurement and infrared spectroscopy. The friction-reducing behavior of the prepared films was examined on a static-dynamic friction coefficient measurement apparatus and on an atomic force microscope. It was found that all the reacted films on the Si substrate showed good friction-reducing ability; especially, the film of the octadecene exhibited the best friction-reducing ability. This was attributed to the transfer of the reacted films onto the counter face with formation of a transfer film on the counterpart surface, which led to the transformation of the sliding between the reacted films and the hard ceramic to fiat between the reacted films and its transfer film on the counterpart surface. The macroscopic and microscopic friction behaviors of the prepared films were dependent on their molecular chain lengths. Thus the octadecene reacted film with the highest degree of ordering arrangement showed the best friction-reducing and antiwear abilities in sliding against Si3N4.

关键词： Alkese Reaction film Hydrogen-terminated silicon Tribological behavior

C_(19)-DITERPENOID ALKALOIDS OF DELPHINIUM MOLLIPILUM

在线全文

学校读者我要写书评

暂无评论

chinese Chemical Letters 1995年第2期6卷 101-102页

作者： Suo Ming ZHANG Qing Yu Ou(lanzhou institute of Chemical {2., chinese academy of sciences, lanzhou 730000) chinese Acad Sci Lanzhou Inst Chem Phys Lanzhou 730000 Peoples R China

Five C19-diterpenoid alkaloids were isolated from the aerial parts of Delphinium mollipilum ***. Four proved to be the known talitine B,talitine A, browniine and delcosine, while the fifth was a new C19-diterpenoid al...

关键词：

中国科学院青岛生物能源与过程研究所2.2.年度“十大工作进展”

在线全文

学校读者我要写书评

暂无评论

高科技与产业化 2024年第9期30卷 20-23页

作者： Qingdao institute of Bioenergy and Process, chinese academy of sciences 中国科学院青岛生物能源与过程研究所

2.2.年,中国科学院青岛生物能源与过程研究所驰骋奋发、勇毅前行,紧紧围绕“四个率先”和“两加快一努力”的目标要求,进一步强化国家战略科技力量主力军使命担当,共同绘就了研究所繁荣发展的辉煌历程,各项事业取得可喜进展。

关键词：中国科学院生物能源工作进展使命担当研究所主力军辉煌历程青岛

Organic geochemical studies of sinking particulate material in China sea area Ⅱ——Geochemical significance of compositional features of ketone, aldehyde and alcohol compounds

在线全文

学校读者我要写书评

暂无评论

chinese Science Bulletin 1997年第22期42卷 1894-1898页

作者： DUAN Yi,CUl Mingzhong, MA Lanhua, SONG Jinming, ZHOU Shixin and LUO Binjie1. lanzhou institute of Geology,{2., lanzhou 730000, China 2. Earthquake Research institute of lanzhou, SSB, lanzhou 730000, China 3. institute of Oceanology,{2., Qingdao 2.6071, China lanzhou institute of Geology Chinese Academy of Sciences Lanzhou China Earthquake Research institute of lanzhou SSB Lanzhou China institute of Oceanology Chinese Academy of Sciences Qingdao China

SINKING particulate organic matter of the sea plays an important role in marine environment. Itnot only provides food for marine organisms and takes part in chemical cycling, but also pro-vides sedimentary organic matter for marine sediments. Therefore, researchers always payclose attention to the source and processes of transport and transformation of marine sinkingparticulate organic matter. Its transport process can be understood by measuring the

关键词： marine sinking paniculate material composition of lipid compounds organic matter source and biochemical pro-cesses.

Separation of protactinium in the reaction of 60MeV/nucleon ^(18)O ions with natural uranium

在线全文

学校读者我要写书评

暂无评论

Nuclear Science and Techniques 2002年第2期13卷 119-124页

作者： YANG Wei-Fan, YUAN Shuang-Gui, XIAO Yong-Hou, XU Yan-Bing, FANG Ke-Ming (institute of modern physics, the chinese academy of sciences,{2.) institute of modern physics the Chinese Academy of Sciences Lanzhou 730000

The activities of protactinium were produced by the multi-nucleontransfer reactions in bombardment of the natural uranium with 60 MeV/nucleon 1sOions. A simple, relatively fast radiochemical procedure was used for extraction sep-aration of protactinium from the uranium and a variety of reaction products using1-phenyl-3-methyl-4-benzoyl-5-pyrazolone and tri-iso-octylamine as extractants. Theγ ray spectrum of the separated protactinium fractions showed that the protactiniumcould be separated from all of the main impurity elements. The decontaminationfactors of the uranium and the main reaction products produced in the reaction aregiven.

关键词：镤 PMBP提取天然铀

Angular Distributions of Projectile Fragmentation in the 600 MeV ^(40)Ar+^(197)Au Reaction

在线全文

学校读者我要写书评

暂无评论

chinese journal of nuclear physics 1995年第1期17卷 24-27页

作者： Liu Guo-xing Dai Guang-xi Chen Ke-liang Yu Xian (institute of modern physics,chinese {2. of sciences,lanzhou 730000) 中科院近代物理所甘肃兰州

The angular distributions of the fragments such as 7Be,2.Na and 2.Mg pro-duced in the 600 MeV 40Ar+197Au reaction are measured using off-line γ-rayspectroscopy *** subtraction of the contribution of fission process,thewidth σp of the transverse momentum distribution is extracted from the analysis of thefragment angular distribution data in the framework of the projectile *** results are compared with the calculated values of Goldhaber statisticalmodel.

关键词： Fragment angular distribution Projectile fragmentation Width σ_p of transverse momentum distribution

Profile of the composition fractions in neutron stars

在线全文

学校读者我要写书评

暂无评论

chinese Science Bulletin 2002年第8期47卷 632-634页

作者： LI Wenfei, ZHANG Fengshou & CHEN LiewenCenter of Theoretical Nuclear physics, National Laboratory of Heavy Ion Accelerator, lanzhou 730000, China {2., chinese academy of sciences, lanzhou 730000, China Department of physics, Shangh Center of Theoretical Nuclear physics National Laboratory of Heavy Ion Accelerator Lanzhou China institute of modern physics Chinese Academy of Sciences Lanzhou China Department of physics Shanghai Jiao Tong University Shanghai China

The composition fractions of β-stable neutron stars and their radial distributions are investigated based on Skyrme-Hartree-Fock theory and Tolman-Oppenheimer-Volkoff (TOV) equation. It is found that a pure neutron interior with a radius of 3.5 km can exist in the neutron stars. When the radius is greater than 3.5 km, the fractions of the proton, electron and μ- appear and increase with the increment of the radius, then decrease after reaching their maximum at the radius of 8 km. These results make it possible to further study the thermal evolution and magnetic properties of the neutron stars.

关键词： neutron stars compositon fractions asymmetric nuclear matter equation of state Tolman-Oppenheimer-Volkoff equation.