检索结果-南通市图书馆

Synthesis and reactions of 4-aryl-1(2H) phtha.a.inones

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 1991年第1期9卷 45-53页

作者： SAYED,M.A. ISLAM,I. MOHAMED,a.a. SOLIMAN,A.Y. BAKEER,H.M. Department of Chemistry Faculty of ScienceAin Shams and El-Azher UniversitiesEgypt Department of Chemistry Faculty of Education at FayoumCairo UniversityEgypt

The behavior of 4-aryl-1(2H)-phtha.a.inones (1a-c) toward some electrophilic and nucleophilic reagents has been described with the aim of preparing some new phtha.a.inone deriva- tives of the expected pharmacological ... 详细信息

关键词： Synthesis and reactions of 4-aryl-1 phtha.a.inones

Some reactions of 4-aryl-1 (2H)-phtha.a.inones

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 1990年第6期8卷 549-554页

作者： SOLIMAN A.Y. BAKEER H.M. SAYED M.A. ISLAM I. MOHAMED a.a. Department of Chemistry Faculty of EducationFayoumEgypt Faculty of Science Ain Shams UniversityCairoEgypt Faculty of Science El-Azher UniversityCairoEgypt

The behayiors of 4-aryl-1 (2H)-phtha.a.inones (1a-c)toward carbon nucleophiles (Grignard reagents) and secondary amine under Mannich conditions as well as the nucleophilic substitution reaction on chlorophtha.a.ine de... 详细信息

关键词： OC Some reactions of 4-aryl-1 phtha.a.inones

放电间隙导通过程中电流通道头部的加速效应（英文）

在线全文

学校读者我要写书评

暂无评论

高电压技术 2015年第2期41卷 534-538页

作者： a.a. Trenkin V.I. Karelin Russian Federal Nuclear Center-VNIIEF

This paper is devoted to expla.a.ion of a phenomenon of current channels heads acceleration which bridges a discharge *** phenomenon was discovered experimentally during some works at investigating nanosecond streamer gas discharges of atmospheric pressure in the air and *** of the bridging process of the discharge gap is presented in the framework of a model of microstructured current *** this case,the channel represents itself as a bunch of microchannels(up to 1 000 and more).Such consideration could be stipulated by the discovered earlier phenomenon of the current channels microstructuring that are realized in the nanosecond discharges of atmospheric *** authors have developed the electro-technical model of the discharge gap bridging by the conducting *** is shown that the channel length dependence of the velocity is linear;this is similar to that of the model of the continuous(unstructured)*** considered and made estimations that stipulate a possibility of gas heating in the microchannels up to the temperatures of associative ionization beginning in the discharge gap bridging *** this case,increase of the charged particles concentration and,consequently,decrease of its resistance cause the head *** is shown that in case of the continuous channel it is impossible to realize the gas heating up to the temperatures of the associative ionization in these *** results reveal the physical reason of the current channels microstructuring as a consequence of the principle of least action manifestation in the area electric breakdown phenomena of the gases.

关键词：摘要编辑部编辑工作读者

中国文学走出去的步伐——苏联解体后中国新时期小说散文在俄罗斯的传播状况

在线全文

学校读者我要写书评

暂无评论

小说评论 2009年第5期 129-137页

作者： a.a.罗季奥诺夫俄罗斯圣彼得堡大学

中国与俄罗斯直接的文化交往已有300多年历史，其间20世纪是中俄文学交流最为活跃的时期。不过，不可否认的是：中国人对俄罗斯文学的了解远远超过俄罗斯人对中国文学的认识，而且20世纪上半叶这种失衡有过客观的历史原因。在中苏关系... 详细信息

中国与俄罗斯直接的文化交往已有300多年历史，其间20世纪是中俄文学交流最为活跃的时期。不过，不可否认的是：中国人对俄罗斯文学的了解远远超过俄罗斯人对中国文学的认识，而且20世纪上半叶这种失衡有过客观的历史原因。在中苏关系蜜月时期的20世纪50年代，中国的古典的和现代的文学开始被大量地介绍给广大苏联读者，并形成了当时文学交流的双向性。

关键词：中国文学苏联解体后俄罗斯人新时期小说传播散文文学交流俄罗斯文学

Study of phase sepa.a.ion in Ga25Se75-xTex chalcogenide thin films

在线全文

学校读者我要写书评

暂无评论

Progress in Natural Science:Materials International 2013年第2期23卷 139-144页

作者： F.A. Al-Agel E.A. Al-Arfaj F.M. Al-Marzouki Shamshad A. Khan a.a. Al-Ghamdi Department of Physics King Abdulaziz University Department of Physics College of Applied Sciences Umm Al-Qura University Department of Physics St. Andrew's College

The effects of composition and thermal annealing in between glass transition and crystallization temperature on the optical and structural properties of Ga25Se75-xTex were investigated. The glass transition and crystallization temperature of the synthesized samples was measured by non-isothermal DSC measurements. Amorphous thin films of Ga25Se75-xTex glasses were grown onto ultra clean glass/Si wafer (100) substrates using the vacuum evaporation technique. The effect of thermal annealing on the optical gap (Eg) for Ga25Se75-xTex thin films in the temperature range 358-388K is studied. As-prepared and annealed thin films were cha.a.terized by X-ray diffraction, field emission scanning electron microscopy, energy dispersive X-ray spectroscopy and optical absorption. Thermal annealing was found to be accompanied by structural effects, which in turn, lead to changes in the optical constants. The optical absorption coefficient (a) for as-deposited and thermally annealed films was calculated from the absorbance da.a. From the knowledge of absorption coefficient at different wavelengths, the optical band gap (Eg) was calculated for all compositions of Ga25Se75-xTex thin films before and after thermal annealing. Results indicate that allowed indirect optical transition is predominated in as-deposited and thermally annealed thin films. The influence of Te incorporation and thermal annealing in Ga25Se75-xTex thin films results in a gradual decrease in the indirect optical gap, this behaviorcan be explained as increased tailing. The decrease in optical band gap and an increase in absorption coefficient and extinction coefficient with thermal annealing can be attributed to transformation from amorphous to crystalline phase.

关键词： Thin films Laser-irradiation Crystallization Phase change Optical band gap

On Non-Classical Problem of Tomography in the Static Potentials Fields

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

On Non-Classical Problem of Tomography in the Static Potenti...

EFFECT OF EMBRYONIC AGE ON’AGGREGABILITY, HISTOGENESIS AND BIOCHEMICAL DIFFERENTIATION IN THE EMBRYONIC CHICK AND QUAIL NEURAL RETINA

International Symposium on Computer Applications in Geoscience

作者： Shvab a.a. Laurentyev Inst.of Hydrodynamics Siberian Division of the USSR of Siences

＜正＞The papers considers the problems with non-classical boundary *** includes the problems with overdefined condition on a part of the body surface and unknown ones on the other of the *** geoscience such problems are known as the continuation problems of the magneticstatic,electrostatic,gravitation and other *** numerical in-

关键词：

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Science in China,Ser.B 1984年第4期27卷 371-379页

作者：李公岫 MOSCONA M.H. MOSCONa.a.A. Institute of Biophysics a.a.emia Sinica Beijing The University of Chicago Department of Biology U.S.A

In this paper, the different ages of the chicken and quail embryonic retina cell aggre-gates are used to examine the aggregation, histogenesis, and the induction of glutamine syn-thetase (GS) elicited by hydrocortisone. The results show that the GS inducibility in theretina cells increases at a slow rate, then rises sharply on the 9th day, and after 9 days,the GS inducibility of aggregates decreases with the increase of embryonic age. The observedvalue of induced GS activity in the chick retina cells coaggregate with quail embryonic retinacells is less than the expected value. Bispecific cell coaggregrates were observed when the9-day chicken embryonic retina cells and the 7(1/2)-day quail embryonic retina cells were com-bined and coaggregated, the chicken and quail cells formed three retinal rosettes. When the9-day chicken embryonic retina cells were commingled with the 13-day quail embryonic retinacells, in the coaggregates, only one retinal rosette was formed.

关键词： EFFECT OF EMBRYONIC AGE ON’AGGREGABILITY HISTOGENESIS AND BIOCHEMICAL DIFFERENTIATION IN THE EMBRYONIC CHICK AND QUAIL NEURAL RETINA

Educational Level in the Light of Human Capital

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Educational Level in the Light of Human Capital

MODEL OF INNOVATIVE ACTIVITY AS THE BASIS OF THE STATISTICAL RESEARCH

作者： Esmukhanova.a.A. Innovative University of Eurasia 102/4 M.Gorky Str.PavlodarKazakhstan140000

Human capital is the most important resource of the postindustrial *** leading to wealth originates from technological knowledge and organizational *** only an experienced working power is ca.a.le to control advance t...

关键词：

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

MODEL OF INNOVATIVE ACTIVITY AS THE BASIS OF THE STATISTICAL...