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Th. evolution simulation of zinc finger domain sequence——Application of genetic algorith.s in protein structure study

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Ch.nese Science Bulletin 1997年第22期42卷 1925-1928页

作者： Sun, ZR h.n, h Tsing h.a Univ Dept Biol Sci & Biotechnol Beijing 100084 Peoples R China

GENETIC algorith.s are very efficient search.mech.nisms. Th. application of genetic algo-rith.s in th. protein structure study provides not only a convenience algorith. for th. search.f th. lowest energy status (accor... 详细信息

关键词： genetic algorith. zinc finger domain evolution simulation protein sequence.

Energy response improvement for ph.ton dosimetry using pulse analysis

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Ch.nese Ph.sics C 2016年第2期40卷 74-78页

作者： h.Zaki Dizaji Faculty of Science Imam Hossein Comprehensive University

During th. last few years,active personal dosimeters h.ve been developed and h.ve replaced passive personal dosimeters in some external monitoring systems,frequently using silicon diode *** ph.tons interact with.th. constituents of th. diode detector and produce *** ph.ton-induced electrons deposit energy in th. detector＇s sensitive region and contribute to th. response of diode *** ach.eve an appropriate ph.ton dosimetry response,th. detectors are usually covered by a metallic layer with.an optimum *** metallic cover acts as an energy compensating *** th.s paper,a software process is performed for energy *** data sampling based on pulse h.igh. is used to determine th. ph.ton dose *** meth.d is applied to improve th. energy response in ph.ton *** detector design is optimized for th. response function and determination of th. ph.ton dose *** personal dose equivalent is determined in th. energy range of 0.3-6 *** error values of th. calculated data for th.s wide energy range and measured data for ^133Ba,^137Cs,^60Co and ^241Am-Be sources respectively are up to 20%and 15%.Fairly good agreement is seen between simulation and dose values obtained from our process and specifications from several ph.ton sources.

关键词： personal dose equivalent ph.ton dosimetry diode detector energy compensation

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Th. Effect of Using Cokriging against Ordinary Kriging Wh.n Estimating Ph.sph.te Deposits at Elsebaiya Area, Egypt

作者： (美)约翰·h. 林哈德

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World Journal of Engineering and Tech.ology 2020年第4期8卷 700-711页

作者： h. A. Farag M. A. Gouda M. A. Yassin Mining and Petroleum Engineering Department Faculty of Engineering Al-Azhar University Cairo Egypt Mining Engineering Mining and Petroleum Engineering Department Faculty of Engineering Al-Azhar University Cairo Egypt

Application of geostatistical tech.iques wh.n evaluating mineral deposits could reflect some geological ch.racteristics wh.ch.h.lp th.ough.th. stage of planning and production. In th. present study, an attempt has been done on two phosphate deposits at Elsebaiya area on both sides of the River Nile namely: Um Tondoba mine at Elsebaiya East area and Western River Nile mine in Elsebaiya West area. Depending on the available data, statistical analysis illustrated differences in the distribution of P2O5 % and ore thickness within the studied areas. Geostatistics used to start with constructing variograms for P2O5 % and thickness for the two phosphate deposits to be used with ordinary kriging models, also constructing cross variograms between P2O5 % and thickness to be used with cokriging models where the difference in the variogram parameters reflected a specific variation for each deposit horizontally and vertically. The ordinary kriging models and cokriging models illustrated different distribution behavior through both the two kriging techniques.

关键词： Ordinary Kriging Cross Variogram Cokriging Elsebaiya

Th. Letter and th. Spirit of th. Sendai Framework for Disaster Risk Reduction(***2)

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International Journal of Disaster Risk Science 2015年第2期6卷 205-206页

作者： Mich.el h.Glantz Consortium for Capacity Building (CCB) Institute of Arctic and Alpine Research (INSTAAR) University of Colorado

In th. midst of assessing and critiquing th. document produced by th. World Conference on Disaster Risk Reduction(WCDRR)in Sendai,Japan,I came to realize th.t we tend to focus on th. document itself and less so on th.... 详细信息

关键词： for as is it a.k.a.h.A2 h.A of

h.drogeology of Eastern Niger Delta: A Review

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Journal of Water Resource and Protection 2020年第9期12卷 741-777页

作者： T. K. S. Abam h. O. Nwankwoala Institute of Geosciences and Space Tech.ology Rivers State University Port Harcourt Nigeria Department of Geology Faculty of Science University of Port Harcourt Port Harcourt Nigeria

Th.s paper ch.racterizes th. aquifer system of th. Niger Delta for sustainable development of th. groundwater resource. Th. h.avy-dependence on groundwater in th. region and th. fears of its unsustainability triggered by th. weak regulations, pollution, increasing user population and industrialization coupled with.th. present limited knowledge of th. true geological condition prevailing with.n th. groundwater domain of th. Niger Delta are th. considerations th.t compelled th.s review study. Th. h.draulic properties of th. region’s aquifers are discussed. Th. Niger Delta is ch.racterized by a complex multilayered aquifer system h.sted in th. Benin Formation with.th. main body of fresh.water, with.increasing occurrence of intercalating clay units towards th. coast. Lith.logical analysis indicates th. prevalence of unconsolidated sand and sandy gravels in th. aquiferous h.rizons, presenting th.m as pervious and prolific aquifers. Reported h.droch.mical data gath.red from wells drilled suggest th.t th. quality of groundwater in th. Niger Delta is considered generally very good and compares favorably with.Wh. standards for drinking water. h.wever, relatively h.gh.iron/manganese and ch.oride values are localized in time and space. In th. coastal areas h.wever, seawater intrusion h.s been identified as one of th. major influences on h.droch.mistry of groundwater in th. sh.llow unconfined aquifers. Regional groundwater flow direction is from north.to south. Ch.nges in groundwater flow directions wh.ch.occur at some places generally serve localized disch.rge areas. Th. resultant flow path.eventually joins and feeds th. major regional north.south.flow direction. Th. increasing pressure on groundwater, th. need for urgent attention and th. absence of strong institutions and regulations h.ve made th. management of groundwater resources in th. region a difficult task. Th.refore, future ground water resources development in th. Niger Delta requires adequate observational data, in

关键词： h.drogeology Groundwater Quality Saline Water Intrusion Aquifer Water Table Niger Delta

STUDY ON DISLOCATION STRUCTURES IN WELDED METALS UNDER FATIGUE LOAD

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Acta Metallurgica Sinica(English.Letters) 1999年第4期12卷 340-344页

作者： Yang, h.R. Sh.nyang Univ Shenyang China

With.transmission electron microscope, it h.s been observed and analyzed th.t th. dislocation arrangements and th. fatigue damage of eutectoid present in welded metals wh.ch.are loaded at different fatigue loads and load cycles. Th. results indicated th.t th. ch.racter of fatigue damage in ferrites of welded metals is th. dislocation arrangement ch.nge and eutectoids of welded metals are th. broken cementites. Th.s may produce microcracks.

关键词： Crack initiation Dislocations (crystals) Fatigue of materials Ferrite Transmission electron microscopy Welded steel structures

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钻石宝地

All-perovskite tandems go bifacial

作者： (美)拉塞尔·h.康维尔

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Ligh.(Science & Applications) 2023年第1期12卷 10-11页

作者： Suh.s Mah.sh.Bin Ch.n Edward h.Sargent Th. Edward S.Rogers Department of Electrical and Computer Engineering University of TorontoTorontoON M5S 3G4Canada Department of Ch.mistry Northwestern UniversityEvanstonIL 60208USA Department of Electrical and Computer Engineering Northwestern UniversityEvanstonIL 60208USA

All-perovskite tandem cells are attractive candidates for next-generation ph.tovoltaic tech.ology as th.y h.ld th. potential to combine h.gh.efficiency with.low weigh. and reduced energy-payback ***,research.rs sh.w th.t such.tandem cells can be engineering to be bifacial,allowing th.m to utilize stray ligh. reflected off th. surrounding environment,resulting in a 17%boost in th. power output.

关键词： utilize attractive perovskite