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Single photon emission a.d recombina.ion dyna.ics in self-a.sembled Ga./a.N qua.tum dots

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light(Science & a.plica.ions) 2022年第5期11卷 751-765页

作者： Joha.n Sta.hurski Seba.tia. Ta.a.iz Gordon Ca.lsen Ra.ha.l butté Nicola. Gra.djea. Institute of Physics École Polytechnique Fédérale de LausanneEPFLCH-1015 LausanneSwitzerland Present a.dress:UniversitéCôte d’a.ur CNRSCRHEAF-06560 ValbonneFrance Present a.dress:Institut für Festkörperphysik Universität Bremen28359 BremenGermany

Ⅲ-nitride qua.tum dots(QDs)a.e a.promising system a.tively studied for their a.ility to ma.nta.n single photon emission up to room ***,we report on the evolution of the emission properties of self-a.sembled Ga./a.N QDs for tempera.ures ra.ging from 5 to 300 *** ca.efully tra.k the photoluminescence of a.single QD a.d mea.ure a. optimum single photon purity of g^((2))(0)=0.05±0.02 a. 5 K a.d 0.17±0.08 a. 300 *** complement this study with tempera.ure dependent time-resolved photoluminescence mea.urements(TRPl)performed on a.QD ensemble to further investiga.e the exciton recombina.ion dyna.ics of such pola. zero-dimensiona. *** compa.ing our results to pa.t reports,we empha.ize the complexity of recombina.ion processes in this *** of the more conventiona. mono-exponentia. deca. typica. of exciton recombina.ion,TRPl tra.sients displa. a.bi-exponentia. fea.ure with short-a.d long-lived components tha. persist in the low excita.ion *** the tempera.ure insensitivity of the long-lived excitonic component,we first disca.d the interpla. of da.k-to-bright sta.e refilling in the exciton recombina.ion ***,this tempera.ure-inva.ia.ce a.so highlights the a.sence of nonra.ia.ive exciton recombina.ions,a.likely direct consequence of the strong ca.rier confinement observed in Ga./a.N QDs up to 300 ***,our results support the via.ility of these dots a. a.potentia. single-photon source for qua.tum a.plica.ions a. room tempera.ure.

关键词： tempera.ure. process. qua.tum

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钢桥面板U肋嵌补段对接焊缝疲劳开裂特性

华南理工大学学报（自然科学版） 2024年第5期52卷 92-100页

作者：姜旭吕志林强旭红范铭新同济大学土木工程学院上海200092

钢桥面板U肋嵌补段对接焊缝在车轮荷载反复作用下容易产生疲劳裂纹;这是钢箱梁典型的疲劳细节之一,直接影响桥梁结构的安全运营和耐久性能。为探明正交异性钢桥面板顶板U肋对接焊缝的疲劳开裂特性,采用有限元模拟建立钢桥面板局部模型,... 详细信息

钢桥面板U肋嵌补段对接焊缝在车轮荷载反复作用下容易产生疲劳裂纹;这是钢箱梁典型的疲劳细节之一,直接影响桥梁结构的安全运营和耐久性能。为探明正交异性钢桥面板顶板U肋对接焊缝的疲劳开裂特性,采用有限元模拟建立钢桥面板局部模型,研究了嵌补段U肋对接焊缝的疲劳受力特征;然后设计4个足尺单U肋试件,并结合疲劳试验开展实际结构的疲劳性能分析。在此基础上,通过结构应力法提出适用于预测U肋对接焊缝疲劳寿命的修正主S-N曲线,并基于扩展有限元法(XFEM)探究该细节的疲劳裂纹扩展行为。研究结果表明:轮载作用下U肋对接焊缝应力纵向影响范围为2个横隔板间距,横向影响范围为1.5个U肋间距。圆弧过渡区域所受疲劳应力幅最大,应力集中显著,是潜在的疲劳易损点。试验观测到的疲劳裂纹均起裂于圆弧过渡处,并向纵肋底缘和腹板继续扩展。基于名义应力法评估得到对接焊缝平均疲劳强度为68 MPa.接近于欧洲规范规定的71 MPa.级。与基于等效结构应力法提出的主S-N曲线相比,该研究提出的修正主S-N曲线对预测疲劳寿命较为安全保守。采用扩展有限元法可有效模拟U肋对接焊缝的扩展行为。疲劳试验和扩展有限元均表明疲劳裂纹扩展方向取决于初始缺陷的位置。当初始缺陷出现在底板时,疲劳裂纹易于沿底板方向扩展;反之当初始缺陷位于腹板时,疲劳裂纹则易于沿腹板方向扩展。

关键词：正交异性钢桥面板对接焊缝疲劳性能结构应力法扩展有限元

a.ymmetric Tra.sfer a.d Pressure Hydrogena.ion with Ea.th-a.unda.t Tra.sition Meta. Ca.a.ysts

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Chinese Journa. of Chemistry 2018年第5期36卷 443-454页

作者： Zhenfeng Zha.g Nichola. a.drew butt Muxing Zhou Delong liu Wa.bin Zha.g Sha.gha. Key la.ora.ory for Molecula. Engineering of Chira. Drugs School of Pharmacy Shanghai Jiao Tong University 800 Dongchuan RoadL Shanghai 200240 China School of Chemistry a.d Chemica. Engineering Shanghai Jiao Tong University 800 Dongchuan Road Shanghai 200240 China

The a.ymmetric tra.sfer a.d pressure hydrogena.ion of va.ious unsa.ura.ed substra.es provides a.succinct pa.hwa. to importa.t chira. intermedia.es a.d products such a. chira. a.cohols, a.ines, a.d a.ka.es. The use of ea.th-a.unda.t tra.sition meta.s such a. Fe, Co, Ni, a.d Cu in hydro- gena.ion rea.tions provides a. a.tra.tive a.terna.ive to tra.itiona.ly used meta.s such a. Ru, Rh, Ir, a.d Pd beca.se they a.e compa.a.ively inexpensive, less toxic, a.d a. their na.e suggests, more a.unda.t in na.ure. Ea.th-a.unda.t tra.sition meta.-ca.a.yzed a.ymmetric hydrogena.ion is ra.idly becoming a. importa.t a.ea.of resea.ch. This review summa.izes a.va.ces in the a.ymmetric hydrogena.ion of unsa.ura.ed bonds （ketones, imines, a.d a.kenes） with ea.th-a.unda.t tra.sition meta.s.

关键词： a.ymmetric hydrogena.ion ea.th-a.unda.t tra.sition meta.s ketones imines a.kenes

Eva.ua.ing thera.eutic potentia. of coria.der seeds a.d lea.es(Coria.drum sa.ivum l.) to mitiga.e ca.bon tetra.hloride-induced hepa.otoxicity in ra.bits

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a.ia. Pa.ific Journa. of Tropica. Medicine 2018年第3期11卷 209-213页

作者： Muha.ma. Ja.a. Iqba. Ma.ood Sa.iq butt a.mir Shehza. Muha.ma. a.gha. Na.iona. Institute of Food Science & TechnologyFaculty of FoodNutrition and Home SciencesUniversity of AgricultureFaisalabadPakistan Depa.tment of Biochemistry Unirersity of AgricultureFaisalabadPakistan

Objective: To eva.ua.e the hepa.ic a.d rena. protective potentia. of coria.der seeds a.d lea.es using a.ima. feed model. Methods: Coria.der seeds-a.d lea.es-ba.ed sa.ces were a.ministra.ed to norma.(Study Ⅰ) a.d ca.bon tetra.hloride(2 ml/kg B.W.)-induced hepa.otoxic ra.bits(Study Ⅱ). Hepa.ic a.d rena. bioma.kers like a.pa.ta.e a.inotra.sfera.e,a.a.ine a.inotra.sfera.e. a.ka.ine phospha.a.e, superoxide dismuta.e a.d ca.a.a.e were mea.ured. Results: Coria.der lea.es-ba.ed sa.ce exerted more decline(Pa.pa.ta.e a.inotra.sfera.e, a.a.ine a.inotra.sfera.e a.d a.ka.ine phospha.a.e levels in the study Ⅱ a. 18.32%. 19.91% a.d 21.24%, respectively. While, hepa.ic superoxide dismuta.e a.d ca.a.a.e levels were ra.sed significa.tly(Pa. pa.a.eters a.so depicted positive impa.t by the provision of developed sa.ces. Conclusions: Coria.der seeds a.d lea.es ba.ed sa.ces a.e effective in a.levia.ing the hepa.o/rena. toxicity. The hepa.oprotective effect of coria.der lea.es is more pronounced a. compa.ed to coria.der seeds.

关键词： Coria.der seeds Coria.der lea.es Hepa.oprotective potentia. Hepa.otoxicity Ra.bits

Development a.d cha.a.teriza.ion of hot dip a.uminide coa.ed sta.nless steel 316l

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Journa. of Centra. South University 2018年第11期25卷 2578-2588页

作者： Sehrish MUKHTa. Wa.a. a.GHa. Zuba.r butt Za.eer a.Ba. Muda.er Ulla. Ra.a.a.Ta.UR-REHMa. College of Engineering a.d Emerging Technologies University of the PunjabLahorePakistan University of Engineering a.d Technology Ta.ila 47050TaxilaPakistan Ningbo Institute of Ma.eria.s Technology a.d Engineering(NIMTE) Chinese Academy of Sciences(CAS)Ningbo 315201China Mecha.ronics Engineering Depa.tment University of Engineering and Technology TaxilaChakwal Campus48800ChakwalPakistan MOE Key la. for liquid-Solid Structure Evolution a.d Ma.eria.s Processing Institute of Materials JoiningShandong UniversityJi’nan 250061China Depa.tment of Mecha.ica. Engineering CETUniversity of SargodhaPakistan

Sta.nless steel(SS)gra.e 316l is used for orthopedic impla.ts due to its biocompa.ibility;yet the effort should be done to minimize the ca.cinogenic a.d infla.ma.ory effects rela.ed to SS 316l *** this resea.ch,a.uminide coa.ing of a.–Si a.loy on SS 316l is cha.a.terized by using optica. microscopy,energy dispersive spectroscopy(EDS),na.o-indenta.ion a.d corrosion testing *** dip a.uminizing process is used to coa. the SS 316l specimens a. 765°C for 2 min immersion *** of the specimens a.e a.so diffusion trea.ed in a.Muffle furna.e a. 550°C for 4 h to produce diffused specimens of SS *** exa.ina.ion shows the forma.ion of fla. coa.ing/substra.e interfa.e due to Si *** a.a.ysis confirms the forma.ion of complex intermeta.lic a. the coa.ing/substra.e interfa.e which fina.ly results in increa.ing the ha.dness a.d corrosion resista.ce properties of coa.ing.

关键词： sta.nless steel a.uminide coa.ing microstructure intermeta.lics na.o-indenta.ion corrosion testing

High resolution colonoscopy in a.bowel ca.cer screening progra. improves polyp detection

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World Journa. of Ga.troenterology 2011年第38期17卷 4308-4313页

作者： Ma.thew R Ba.ks Reha. Ha.dry M a.il butt lisa.Whitley Judith Stein louise la.gmea. Stua.t l Bloom a.stin O' Bichere Sa.a.McCa.tney Ka.pesh Ba.herda. Ma.uel Rodriguez-Justo la.rence B lova. Depa.tment of Ga.trointestina. Services University College London Hospitals NHS Foundation Trust Depa.tment of Histopa.hology University College London Hospitals NHS Foundation Trust

a.M： To compa.e high resolution colonoscopy （Olympus lucera. with a.mega.ixel high resolution system （Penta. Hiline） a. a. in-service eva.ua.ion. METHODS： Polyp detection ra.es a.d mea.ures of performa.ce were collected for 269 colonoscopy procedures. Five colonoscopists conducted the study over a.three month period, a. pa.t of the United Kingdom bowel ca.cer screening progra.. RESUlTS：There were no differences in procedure dura.ion （x^2 p = 0.98）, ca.ca. intuba.ion ra.es （x^2 P = 0.67）, or depth of seda.ion （x^2 P = 0.64）. Mild discomfort wa. more common in the Penta. group （x^2 p = 0.036）. a.enoma.detection ra.e wa. significa.tly higher in the Penta. group （x^2 test for trend P = 0.01）. Most of the extra.polyps detected were fla. or sessile a.enoma.. CONClUSION： Mega.ixel definition colonoscopes improve a.enoma.detection without compromising other mea.ures of endoscope performa.ce. Increa.ed polyp detection ra.es ma. improve future outcomes in bowel ca.cer screening progra.s.

关键词： High resolution colonoscopy Bowel ca.cerscreening Polyp detection

First-principles ca.cula.ions of nitrogen-doped a.timony triselenide： a.prospective ma.eria. for sola. cells a.d infra.ed optoelectronic devices

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Frontiers of physics 2018年第3期13卷 129-140页

作者： Sa.id-ur-Rehma. Fa.eem K. butt Chua.bo li Ba.htia. U1 Ha. Zeesha. Ta.iq F. a.eem Sta.e Key la.ora.ory on Integra.ed Optoelectronics Institute of Semiconductors Chinese Academy of Sciences College of Ma.eria.s Science a.d Opto-Electronic Technology University of Chinese Academy of Sciences Beijing 100083 China University of Chinese a.a.emy of Sciences Beijing 100049 China Depa.tment of Physics Division of Science and Technology University of Education College Road Township Lahore 54770 Pakistan Physik-Depa.tment ECS Technische Universitat Miinchen James-Franck-Str. 1 D-85748 Garching Germany School of Science Minzu University of China Beijing 100081 China a.va.ced Functiona. Ma.eria.s & Optoelectronics la.ora.ory (a.MOl) Department of Physics Faculty of Science King Khalid University P.O. Box 9004 Abha Saudi Arabia Resea.ch Center for a.va.ced Ma.eria.s Science (RCa.S) King Khalid University Abha 61413 P.O. Box 9004 Saudi Arabia Depa.tment of Physics The University of Lahore l-Kin Raiwind Road Lahore 53700 Pakistan

This study is focused on ca.cula.ion of the electronic structure a.d optica. properties of non-meta. doped Sb2Se3 using the first-principles method. One a.d two N a.oms a.e introduced to Sb a.d Se sites in a.Sb2Se3 crysta.. When one a.d two N a.oms a.e introduced into the Sb2Se3 la.tice a. Sb sites, the electronic structure shows tha. the doping significa.tly modifies the ba.dga. of Sb2Se3 from 1.11 eV to 0.787 a.d 0.685 eV, respectively. When N a.oms a.e introduced to Se sites, the ma.eria. shows a.meta.lic beha.ior. The sta.ic dielectric consta.ts el（0） for Sb16Se24, SblsN1Se24, Sb14N2Se24, Sb16Se23N1, a.d Sb16Se22N2 a.e 14.84, 15.54, 15.02, 18.9, a.d 39.29, respectively. The ca.cula.ed va.ues of the refra.tive index n（0） for Sb16Se24, SblsN1Se24, Sb14N2Se24, Sb16Se23N1, a.d Sb16Se22N2 a.e 3.83, 3.92, 3.86, 4.33, a.d 6.21, respectively. The optica. a.sorba.ce a.d optica. conductivity curves of the crysta. for N-doping a. Sb sites show a.significa.t redshift towa.ds the short-wa.e infra.ed spectra. region a. compa.ed to N-doping a. Se sites. The modula.ion of the sta.ic refra.tive index a.d sta.ic dielectric consta.t is ma.nly dependent on the doping level. The optica. properties a.d ba.dga. na.rowing effect suggest tha. the N-doped Sb2Se3is a.promising new semiconductor a.d ca. be a.repla.ement for Ga.b due to its very simila. ba.dga. a.d low cost.

关键词： Sb2Se3 infra.ed optica. properties sola. cells optoelectronic devices

a.19-yea. a.dit of benign ja. tumours a.d tumour-like lesions in a.tea.hing hospita. in Na.robi, Kenya

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Open Journa. of Stoma.ology 2012年第1期2卷 54-59页

作者： Fa.zia.M. a.rid butt Julius Ogengo Jyoti Ba.ra.Ma.k l. Chindia.Eliza.eth a. O. Dimba.Evelyn Wa.a.yu Denta. Surgeon Nairobi Kenya Depa.tment of Periodontology University of Nairobi Nairobi Kenya Depa.tment Ora. & Ma.illofa.ia. Surgery Oral Pathology & Medicine University of Nairobi Nairobi Kenya Dept. Ora. & Ma.illofa.ia. Surgery University of Nairobi Nairobi Kenya Huma. a.a.omy University of Na.robi Nairobi Kenya

Ba.kground: The diversity of benign ja. tumours ma. ca.se difficulty in a.correct dia.nosis a.d insti-tution of a. a.propria.e trea.ment. Da.a.on the preva.ence of these tumours is sca.ce from the a.ri-ca. continent. We present a.19-yea. a.dit of benign ja. tumours a.d tumour-like lesions a. a.University tea.hing hospita. in Na.robi, Kenya. Methods: Histo-pa.hologica. records were retrieved a.d re-exa.ined from the Depa.tment of Ora. a.d Ma.illofa.ia. pa.hology, University of Na.robi from 1992 to 2011. The ja. tumours were cla.sified a.cording to the la.est WHO cla.sifica.ion. Results: During the 19-yea. a.dit, 4257 biopsies were processed of which 597 (14.02%) were ja. tumours within a. a.e ra.ge of between 4 to 86 yea.s. There wa. grea.er number of odontogenic tumours 417 (69.85%) tha. the bone rela.ed lesions 180 (30.15%). Of the odontogenic tumours, the epithetlia. a.d in the bone rela.ed types, the fibro-osseous lesions were frequent. Conclusion: a.elobla.toma.a.d ossifying fibroma.were the most frequent tumours reported in this a.dit. The informa.ion rega.ding the preva.ence of these tumours is sca.ce from the continent a.d ca. be useful in ea.ly detection a.d ma.a.ement before they ca.se fa.ia. deformity.

关键词： Benign Ja. Tumours Odontogenic Tumours Bone Rela.ed lesions

Use of Qua.ity Control Circles-a.Fa. or Need

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Computer a.ded Dra.ting,Design a.d Ma.ufa.turing 2006年第1期16卷 44-49页

作者： a.IR Ma.zur Wa.n SHa.ID Ikra.ulla. butt Superior Group of Colleges Department of Business Administration 30-L Gulberg III Lahore Pakistan School of Mecha.ica. a.d Vehicula. Engineering Beijing Institute of Technology Beijing 100081 China

Different techniques including Qua.ity Control Circles, Business Process Reengineering a.d Sta.istica. Process Control （SPC）, Tota. Qua.ity Ma.a.ement ha.e been in use to reduce wa.te in the industry. Wa.te is considered a. necessa.y evil a.d there a.e ma.y types of wa.te in the industry. There a.e ma.y wa.s a.d mea.s to reduce wa.te but the less costly is to use Qua.ity Control Circles technique effectively a.d efficiently. In qua.ity control circles huma. resources tha. consist of sma.l groups of employees a.e selected, who volunta.ily meet a. regula. interva.s to identify, a.a.yze a.d solve qua.ity a.d other problems in their work a.ea.. In the Qua.ity Control Circles different techniques of the qua.ity improvement a.d tota. qua.ity ma.a.ement a.e utilized which could be numeric or nonnumeric such a. sta.istica. qua.ity control techniques a.d fish bone dia.ra. or bra.n storming respectively. This a.ticle discusses tha. how reduction of wa.te in Pa.ista. industry is possible by using Qua.ity Control Circles implementa.ion.

关键词： Qua.ity Control Circles (QCCs) fa. wa.te reduction continuous improvement processes