检索结果-南通市图书馆

Fa.rica.ion of Dye Sensitized Sola. Cell Ba.ed on Tita.ium Dioxide (TiO2)

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

a.va.ces in Ma.eria.s Physics a.d Chemistry 2015年第9期5卷 361-367页

作者： ari a. mohammed a.a. S. Sa.d a.ma. Wa.a. a. a.eez Depa.tment of Physics Faculty of Science University of Zakho Duhok Iraq

The Dye Sensitized Sola. Cell (DSSC) pla.s a. importa.t role beca.se of low ma.eria. cost, ea.e of production a.d high conversion efficiency a. compa.ed to other thin-film sola. cell technologies. The ma.n objective is to crea.e a.d find the best configura.ion of the sola. cell ba.ed on ma.eria.s tha. a.e inexpensive a.d highly efficient in sola. energy conversion a.d subsequently test the efficiency of dye sensitized tita.ium dioxide sola. cell. We begin the process with two gla.s pla.es coa.ed with Fluorine tin oxide (FTO). Tita.ium dioxide is a.plied to the conductive side of one pla.e a.d the other pla.e is coa.ed with gra.hite. a.dye is a.sorbed on to the TiO2 la.er a.d then the pla.es a.e sa.dwiched together. a.drop of iodide electrolyte is then a.ded between the pla.es. The tests ca.ried out indoors under a.la.p emitting a.l wa.elengths in the visible spectrum were not found to provide consistent da.a.due to substa.tia. hea.ing of the cell. The outdoor tests ca.ried out in na.ura. sunlight exhibited stea.y volta.e a. much higher level. Future resea.ch will involve the incorpora.ion of qua.tum dots instea. of the orga.ic dye a. a.sensitizer. Qua.tum dots ha.e the a.va.ta.es of providing tuna.le ba.d ga.s a.d the a.ility to a.sorb specific wa.elength.

关键词： Tra.spa.ent Conducting Gla.s Tita.ium Dioxide (TIO2) Na.opa.ticles Orga.ic Dyes Electrolyte

The Effect of Doped Indium on the Electrica. a.d Optica. Properties of (Se0.7Te0.3)1&a.p;minus;xInxThin Films

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

a.va.ces in Ma.eria.s Physics a.d Chemistry 2015年第4期5卷 140-149页

作者： Muha. Ta.ib a.dulla. a.a. S. Sa.d a.ma. ari a. mohammed Depa.tment of Physics Faculty of Science University of Zakho Duhok Iraq

In-doped (Se0.7Te0.3) thin films (In: 0, 0.05, a.d 0.08wt%) with thickness of (150 ± 25 nm) ha.e been deposited on gla.s substra.es by chemica. va.or deposition by using selenium, tellurium a.d indium whose purity is (99.99%) compound a.loy. The electrica. a.d optica. properties of the thin films were a.a.yzed. The effects of In-doping concentra.ion on the thermoelectric properties of the thin films were investiga.ed by room-tempera.ure mea.urement of the See beck coefficient a.d electrica. resistivity. The thermoelectric power fa.tor shows the best result a. 0.05wt% in doping. The See beck coefficients a.e positive with increa.ing in doping concentra.ion from 0 to 0.08wt%. a.d the thin films show p-type conduction. For optica. properties, the tra.smission of a.l sa.ples wa. a.proxima.ed to 90%.

关键词： Selenium Tellurium Indium p-Type Fermi-Level

a.Compa.a.ive Study of Ea. Disea.es in School Children from Lower versus Higher Socioeconomic Sta.us

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Interna.iona. Journa. of Otola.yngology a.d Hea. & Neck Surgery 2021年第2期10卷 107-118页

作者： Yoha.na.Ma.riga.Ta.woingi mohammed Bello Fufore a.uba.a. Uma. Ga.sari Emma.uel Musa.Wuni ari Thimnu Isa. a.dulla.i Depa.tment of ENT City Hospital Birmingham UK Depa.tment of ENT Federal Medical Centre Yola Nigeria Depa.tment of ENT University of Maiduguri Teaching Hospital Maiduguri Nigeria

Ba.kground: Preventa.le otologic conditions ha.e been found to be importa.t hea.th issues a.ong pa.dia.ric a.e group. Poor socioeconomic sta.us a.d ina.propria.e ma.a.ement services in developing countries lea. to various complica.ions despite the fa.t tha. most of these disea.es a.e self-limiting. The a.m of this study wa. to determine the preva.ence a.d pa.tern of ea. disea.es in school children of high a.d low socioeconomic sta.us in Yola. Nigeria. Methods: This study wa. conducted in Ma.ch 2017 in two prima.y schools (priva.e a.d public) in Yola.a.ong 6 - 8 yea.s old pupils. a.prova. for the study wa. obta.ned from Federa. Medica. Centre, Yola.a.d consent wa. obta.ned from the pa.ents/gua.dia.s a.d the school a.thorities. Using a.hea.th questionna.re, a.brief ENT history wa. obta.ned from children in yea.s 1 a.d 2 of ea.h school. Otoscopic exa.ina.ion, a.diometry a.d tympa.ometry were then ca.ried out. Da.a.collected wa. a.a.ysed using SPSS version 20. Results: One hundred a.d three children were studied. The a.e ra.ge wa. 6 - 8 with mea. a.e of 6.8 ± 0.9 a.d 53 (51.5%) boys. Fifty-two (50.5%) were from public school (low socio-economic cla.s) a.d 51 (49.5%) from priva.e (high socia. cla.s). Wa. wa. the most common ea. condition encountered a.fecting 37 (35.9%) children, a.d the number wa. simila. in both groups. Otitis media.with effusion (OME) wa. encountered in seven children evenly split between the two groups showing a.point incidence of 6.8%. There wa. hearing loss in 13 (12.6%) children, a.d this wa. a.so simila. in the two groups. Conclusion: Wa. impa.tion wa. the commonest otologic disea.e encountered. Our study a.so showed a.point incidence of 6.8% for OME, but there wa. no sta.istica. difference between the two groups, a.d neither wa. there a.y sta.istica.ly significa.t difference between the two groups in a.y of the other disea.es encountered.

关键词： Children Glue-Ea. Hearing Loss Socia. Sta.us Wa.

不同抛光方式对去除托槽后牙釉质表面影响的研究

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

不同抛光方式对去除托槽后牙釉质表面影响的研究

作者： La.IB Ha.a. mohammed GHa.EB 中国医科大学

学位级别：硕士

目的:固定矫治结束时,需要去除托槽和牙齿表面的粘结剂以便恢复牙齿的美观和健康。去除粘结剂时,一方面要尽可能地去除干净以恢复牙面的光洁,预防牙菌斑滞留,另一方面更要防止损伤牙釉质。因此,选择合适的车针以及有效评估去除效果具有... 详细信息

目的:固定矫治结束时,需要去除托槽和牙齿表面的粘结剂以便恢复牙齿的美观和健康。去除粘结剂时,一方面要尽可能地去除干净以恢复牙面的光洁,预防牙菌斑滞留,另一方面更要防止损伤牙釉质。因此,选择合适的车针以及有效评估去除效果具有一定的临床意义。本研究旨在应用放大镜对应用不同种类车针去除粘结剂的效果进行评价,以期对今后临床相关操作有所启示。方法:从中国医科大学附属口腔医院门诊收集因正畸需要拔除的前磨牙60颗,随机分为3组,每组n=20。TC组(用碳化钨车针去除粘结树脂)、SD组(用软盘车针去除粘结树脂)、DB组(用金刚石车针去除粘结树脂)。将每组各分为两个亚组(每亚组n=10),肉眼组(NTC、NSD、NDB)在肉眼直视下操作;放大镜组(MTC、MSD、MDB)借助放大镜进行操作。使用Tra.sbond XT正畸粘结剂粘接金属托槽,24小时后用去托槽钳去除托槽,评估牙面粘结剂残余指数(ari)。再分别使用不同的车针去除残余的粘结剂,以秒为单位记录去胶时间,最后均用矽粒子进行抛光。应用Mitutoyo SJ-210轮廓仪对每个亚组进行评估,以确定牙齿平均表面粗糙度(Ra.,在扫描电子显微镜(SEM)下确定牙釉质损伤指数(EDI)并评分。评估在三个时间点进行:粘接前(T0)、去除粘结剂后(T1)、抛光后(T2)。结果:Kruska.-Wa.lis检验显示各研究组ari无统计学差异(P>0.05)。方差分析显示,与肉眼组相比,放大镜组去除粘结树脂所需的时间显著减少(Pa.值差异无统计学意义(P>0.05),T1、T2时Ra.值差异有统计学意义(Pa.两两比较,除T1时NTC-NSD、NTC-MSD、NSD-MSD差异无统计学意义(P>0.05),其余各组间差异均有统计学意义(Pa.仍略高于其他亚组,其他亚组间差异无统计学意义(P>0.05)。T0、T1、T2的表面粗糙度两两比较显示,NDB和MDB在T1时的Ra.值与T0、T2时比较,差异有统计学意义(Pa.值比较,差异无统计学意义(P>0.05)。而在NDB和MDB中,T0、T1、T2的表面粗糙度Ra.均值差异有统计学意义(P0.05)。结论:1.低速碳化钨车针与软盘车针相当,可作为金刚石车针的替代品。2.金刚石车针在肉眼直视下操作会对牙釉质造成严重的损伤,而借助放大镜进行操作可以减轻对牙釉质的损伤。3.矽粒子抛光步骤可以使肉眼直视下操作的牙齿表面更光滑。4.无论使用哪种类型的车针去除粘结剂,借助放大镜进行操作都更好。

关键词：正畸去托槽粘结剂残留抛光牙釉质

基于Ra.SE模型CFD预测E779a.螺旋桨空化及其在通用船体后的水动力性能

同方学位论文库评论

在线全文

同方学位论文库

学校读者我要写书评

暂无评论

哈尔滨工程大学学报（英文版） 2023年第2期22卷 273-283页

作者： mohammed a.na. Rizk Sa.ir E.Belhenniche Oma. Imine Omer Kema. Kina.i Fa.ulty of Mecha.ica. a.d Electrica. Engineering Maritime Engineering DepartmentTishreen UniversityLattakiaSyria Na.a. a.ro-Hydrodyna.ic La.ora.ory Marine Engineering DepartmentUSTO MBOran 31000Algeria a.rona.tics a.d Propulsion Systems La.ora.ory Mechanical Engineering DepartmentUSTO MBOran 31000Algeria Fa.ulty of Na.a. a.chitecture a.d Ocea. Engineering Istanbul Technical UniversityIstanbul 34469Turkey Depa.tment of Mecha.ronics Engineering Istanbul Technical UniversityIstanbul 34469Turkey Marine Cybernetics a.va.ced Vehicle Technologies(Ma.NETICS) ITU ARI TeknokentIstanbul 34349Turkey

Ship propulsion performa.ce hea.ily depends on ca.ita.ion,increa.ing the recent interest in this field to lower ship *** resea.ch on the effects of ca.ita.ion is genera.ly ba.ed on the open-wa.er propeller performa.ce but the intera.tions of the ca.ita.ing propeller with the ship hull significa.tly a.fect the propulsion performa.ce of the *** this study,we first investiga.e the INSEa. E779a.propeller by a.Ra.SE-ba.ed CFD in open-wa.er *** numerica. implementa.ion a.d the selected grid a.ter sensitivity a.a.ysis pa.tia.ly succeeded in modeling the ca.ita.ing flow a.ound the *** a.reement wa. observed compa.ed to experimenta. ***,using the open-wa.er da.a.a. input,the propeller’s performa.ce behind a.full-sca.e ship wa. ca.cula.ed under self-propulsion *** being a. undesired incident,we found a.ra.e condition in which ca.ita.ion enha.ces propulsion ***σ=1.5;the propeller rota.ion ra.e wa. lower,while the thrust a.d torque coefficients were higher.

关键词： Ca.ita.ion Marine propeller Propulsion efficiency Propeller-hull intera.tion INSEa. E779A

a.Compa.a.ive Study of Ea. Disea.es in School Children from Lower versus Higher Socioeconomic Sta.us

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论