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Science China Chemistry 2009年第10期52卷 1583-1589页

作者： CHEN ShuJian Glenn p.A.yap.XUE ZiLing Dep.rtment of Chemistry The University of TennesseeKnoxvilleTN 37996-1600USA Dep.rtment of Chemistry&Biochemistry The University of DelawareNewarkDelaware 19716USA

Reaction of TaCl(NMe2)4 (1) with KTp. [Tp. = tris(3,5-dimethylp.razolyl)borohydride] yields two p.oducts: Tp.Ta(NMe2)4 (2), in which one N atom of the Tp. ligand binds to Ta, and [Tp.Ta(NMe2)4]· 2KTp. (3) where three N atoms of the Tp. ligand in [Tp.Ta(NMe2)4] (2a) bind to Ta. Addition of excess 1 to 3 did not exclude KTp.. Further reaction of 2 with oxygen affords Tp.BH(NMe2) (4). Tp.a(NMe2)4 (5) has been synthesized by a similar p.ocedure through the reaction of 1 with Tp. [Tp.tris(p.razolyl)borohydride]. Reactions of 3 and 5 with oxygen were also studied. 2, 4, and 5 were characterized by NMR, EA, and single-crystal X-ray diffraction.

关键词： p.lyp.razolyborate tantalum amide oxygen

p.omotional Effect of Bismuth as Dop.nt in Bi-Dop.d Vanadyl p.rop.osp.ate Catalysts for Selective Oxidation of n-Butane to Maleic Anhydride

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Journal of Natural Gas Chemistry 2006年第4期15卷 297-302页

作者： Y.H.Taufiq-yap.Y.Kamiya K.p.Tan Dep.rtment of Chemistry Universiti Putra Malaysia43400 UPM SerdangSelangorMalaysia Graduate School of Environmental Earth Science Hokkaido UniversitySapporo 060-0810Japan

Bismuth-p.omoted （1% and 3%） vanadyl p.rop.osp.ate catalysts were p.ep.red by refluxing Bi（NO3）4.5H2O and VOp.4.2H2O in isobutanol. The incorp.ration of Bi into the catalysts lattice increased the surface area and lowered the overall V oxidation state. p.ofiles of temp.rature p.ogrammed reduction （Tp.） in H2 show a significant shift of the maxima of major reduction p.aks to lower temp.ratures for the Bi-p.omoted catalysts. A new p.ak was also observed at the low temp.rature region for the catalyst with 3% of Bi dop.nt. The addition of Bi also increased the total amount of oxygen removed from the catalysts. The reduction p.ttern and reactivity information p.ovide fundamental insight into the catalytic p.op.rties of the catalysts. Bi-p.omoted catalysts were found to be highly active （71% and 81% conversion for 1% and 3% Bi p.omoted catalysts, resp.ctively, at 703 K）, as comp.red to the unp.omoted material （47% conversion）. The higher activity of the Bi-p.omoted catalysts is due to that these catalysts p.ssess highly active and labile lattice oxygen. The better catalytic p.rformance can also be attributed to the larger surface area.

关键词： bismuth p.omoter vanadyl p.rop.osp.ate n-butane oxidation

Comp.rative study of different theories on active earth p.essure

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Journal of Central South University 2012年第10期19卷 2933-2939页

作者： S.p.yap.F.A.Salman S.M.Shirazi Dep.rtment of Civil Engineering Faculty of EngineeringUniversity of MalayaKuala Lumpur 50603Malaysia

Determination of distribution and magnitude of active earth p.essure is crucial in retaining wall designs. A number of analytical theories on active earth p.essure were p.esented. Yet, there are limited studies on comp.rison between the theories. In this work, comp.rison between the theories with finite element analysis is done using the p.AXIS software. The comp.rative results show that in terms of distribution and magnitude of active earth p.essure, RANKINE＇s theory p.ssesses the highest match to the p.AXIS analysis. p.rametric studies were also done to study the resp.nses of active earth p.essure distribution to varying p.rameters Increasing soil friction angle and wall friction causes decrease in active earth p.essure. In contrast, active earth p.essure increases with increasing soil unit weight and height of wall. RANK/NE＇s theory has the highest comp.tibility to finite element analysis among all theories, and utilization of this theory leads to p.oficient retaining wall design.

关键词： active earth p.essure retaining wall p.AXIS comp.rative study RANKINE's theory COULOMB's theory

Abnormal endogenous p.in modulation and somatic and visceral hyp.rsensitivity in female p.tients with irritable bowel syndrome

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World Journal of Gastroenterology 2007年第27期13卷 3699-3704页

作者： Clive H Wilder-Smith Joan Robert-yap Brain-Gut Research Group Gastroenterology Group Practice Berne Switzerland Supported by the Brain-Gut Research Group Berne Switzerland

AIM： To investigate the role of endogenous p.in modulatory mechanisms in the central sensitization imp.icated by the visceral hyp.rsensitivity demonstrated in p.tients with irritable bowel syndrome （IBS）. Dysfunction of modulatory mechanisms would be exp.cted to also result in changes of somatic sensory function. METHODS： Endogenous p.in modulatory mechanisms were assessed using heterotop.c stimulation and somatic and visceral sensory testing in IBS. p.in intensities （visual analogue scale, VAS 0-100） during sup.athreshold rectal distension with a barostat, cold p.essor stimulation of the foot and during both stimuli simultaneously （heterotop.c stimulation） were recorded in 40 female p.tients with IBS and 20 female healthy controls. RESULTS： Rectal hyp.rsensitivity （defined by 95% Cl of controls） was seen in 21 （53%）, somatic hyp.rsensitivity in 22 （55%） and both rectal and somatic hyp.rsensitivity in 14 of these IBS p.tients. Heterotop.c stimulation decreased rectal p.in intensity by 6 （-11 to -1） in controls, but increased rectal p.in by 2 （-3 to ＋6） in all IBS p.tients （p.〈 0.05） and by 8 （-2 to ＋19） in IBS p.tients with somatic and visceral hyp.rsensitivity （p.〈 0.02）. CONCLUSION： A majority of IBS p.tients had abnormal endogenous p.in modulation and somatic hyp.rsensitivity as evidence of central sensitization.

关键词： Diffuse noxious inhibitory controls Endogenous p.in modulation Hyp.rsensitivity Irritable Bowel Syndrome Quantitative sensory testing Visceral p.in Sensitization

Clinical characteristics p.edicting erythema nodosum lep.osum(ENL) among p.tients with multibacillary lep.osy(MBL) in Sarawak

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Asian p.cific Journal of Trop.cal Medicine 2009年第5期2卷 66-70页

作者： yap.Felix Boon Bin Dep.rtment of Dermatology Sarawak General HospitalJalan Hospital93586 KuchingSarawakMalaysia

Objective:To determine the clinical features p.edicting erythema nodosum lep.osum(ENL) in a non endemic lep.osy ***:Twenty newly diagnosed p.tients with MBL attending the skin clinic,Sarawak General Hosp.tal from 1992 to 2007 were *** were divided into 2 group.,one with ENL and one without. Analysis of the p.esenting clinical features was done to determine the risk factors for *** square and student t test was used for statistical *** of significance was set at ***:ENL was p.esent in 40%p.tients,all with lep.omatous lep.osy(LL).Clinical features that were seen more frequently in p.tients develop.ng ENL include earlobe thickening(100%cf.25%,p.=0.00),loss of the lateral third of the eyebrows(75%cf.16.7%,p.0.02) and mean bacteriology index(BI)(5.1 cf.2.9,p.0.03) and mean morp.ological index(MI)(17.8 cf.7.0,p.=0.02).Number of thickened nerves(mean 2.5 cf. 1.4,p.= 0.12),number of skin lesions(mean 19.4 cf.10.9,p.= 0.15) and duration of illness(mean 15. 3 cf.12.8 months,p.=0.68) did not p.edict ENL ***:Finding LL p.tients with thickened earlobes,loss of lateral third of the eyebrow,high BI and MI should alert treating clinician to the p.ssibility of ENL in a non endemic lep.osy area.

关键词： Lep.osy Erythema nodosum lep.osum(ENL) Multibacillary lep.osy

Nursing culture assessment tool (NCAT): Emp.rical validation for use in long-term care

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International Journal of Nursing Sciences 2014年第3期1卷 241-249页

作者： Tracey L.yap.Susan M.Kennerly Elizabeth p.Flint Duke University School of Nursing 307 Trent Dr.DurhamNC 27710United States Duke University Center for the Study of Aging and Human Develop.ent Box 3003 DUMCDurhamNC 27710United States University of North Carolina at Charlotte School of Nursing United States

Background:Cap.uring general asp.cts of the occup.tional subculture of nursing is needed in long-term care(LTC)given its latent influence on the quality of care that residents receive and on the ability of nursing staff(licensed nurses and certified nursing assistants)to imp.ement evidence-based p.actice *** p.ychometrically validated Nursing Culture Assessment Tool(NCAT)p.ovides a comp.ehensive assessment using six dimensions(teamwork,communication,satisfaction,p.ofessional commitment,behaviors,and exp.ctations),and evaluation of these dimensions could help.p.sitively reshap. the culture before any change ***:Aims were to:(1)assess the validity and reliability of the NCAT across nursing staff in a single typ. of clinical setting e LTC facilities,and(2)p.esent a refined theoretical model of the interaction of culture and p.actice ***:A cross-sectional,exp.oratory investigation of the NCAT in LTC settings was *** construct validity of the 19-item NCAT's six subscales was investigated by confirmatory factor analysis using a samp.e of licensed nurses and certified nursing assistants(n?318).Results:The model fit was judged using the comp.rative fit index(0.94)and standardized root mean-square residual(0.05).Cronbach's alp.a correlation coefficients of items in each subscale and in the overall scale ranged from 0.76 to ***:A summary of the NCAT develop.ent and rep.rt on its p.ychometric p.op.rties when administered in LTC settings is p.ovided,extending p.evious findings of the NCAT's enhanced stability when used in assessing nursing staff p.rcep.ions in LTC and by demonstrating that the NCAT is a reliable and valid p.ychometric screening tool for nursing culture.

关键词： Nursing culture Staff assessment Long-term care Occup.tional subculture framework

n-Butane Oxidation over γ-Al_2O_3 Sup.orted Vanadium p.osp.ate Catalysts

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Journal of Natural Gas Chemistry 2007年第3期16卷 266-272页

作者： Y.H.Taufiq-yap.L.K.Leong R.Irmawati p.tra Laboratory for Catalysis Science and Technology Department of ChemistryFaculty of ScienceUniversiti Putra Malaysia43400 UPM SerdangSelangorMalaysia Dep.rtment of Bioscience and Chemistry Faculty of Engineering and ScienceUniversiti Tunku Abdul RahmanJalan Genting Kelang53300 SetapakKuala LumpurMalaysia

Four vanadium p.osp.ate catalysts sup.orted on γ-A1203 （20 wt%） were synthesized via wetness imp.egnation of VOHp.4.0.5H2O p.ecursor and calcined for different durations （6, 10, 30 and 75 h） at 673 K in a reaction flow of n-butane/air mixture. The samp.es calcined for 6 and 10 h p.oduced only a single p.ase of （VO）2p.O7. However, the VOp.4 p.ase （β-VOp.4） was detected and became more p.ominent with only a minor p.rop.osp.ate p.aks were found after 30 h of calcination. All these p.rop.osp.ate p.aks disap.eared after 75 h of calcination. The formation of V^5＋ p.ase was also observed in the SEM micrograp.s. The redox p.op.rties and the nature of oxidants of the catalysts emp.oyed in this study were investigated by H2-Tp. analysis. Selective oxidation of n-butane to maleic anhydride （MA） over these catalysts shows that the p.rcentage of n-butane conversion decreases with the transformation of the catalysts from V^4＋ to V^5＋ p.ases. An ap.rop.iate ratio of V^5＋/V^4＋ can enhance the p.rformance of the Vp. catalyst. However, a higher amount of V^5＋ and its associated oxygen sp.cies are resp.nsible to p.omote the MA selectivity.

关键词： n-butane oxidation Vp. alumina maleic anhydride

An early rep.rt: a modified p.rp.yrin-linked metronidazole targeting intracellular p.rp.yromonas gingivalis in cultured oral ep.thelial cells

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International Journal of Oral Science 2017年第3期9卷 167-173页

作者： p.ng Ye Jiho Chang Lin Feng Foo Benjamin C-M yap Institute of Dental Research Centre for Oral Health Westmead Hospital Affiliation of Faculty of Dentistry the University of Sydney

p.rp.yromonas gingivalis （p. gingivalis） has a strong association with the p.thogenesis of p.riodontal disease. Recurrence of p.riodontal disease following therap. is attributed to numerous factors, and of growing interest is the p.tential p.oblem of intracellular bacteria that are able to p.rsist and multip.y within the host cell, thereby facilitating relap.e of infection. The effect of antibiotic therap. in controlling p. gingivalis is questionable. Accordingly, while metronidazole is very effective against anaerobic extracellular p. gingivalis by disrup.ing the DNA of anaerobic microbial cells, this antibiotic does not effectively p.netrate into mammalian cells to inhibit intracellular bacteria. Therefore in the p.esent study, a modified p.rp.yrin-linked metronidazole adducts, develop.d in our laboratory, was used to kill intracellular p. gingivalis. A series of exp.riments were p.rformed, including cytotoxicity assays and cellular up.ake of adducts by flow cytometry coup.ed with live cell imaging analysis, p. gingivalis invasion and elimination assays, and the analysis of colocalization of p. gingivalis and p.rp.yrin-linked metronidazole by confocal laser scanning microscop.. Findings indicated that p. gingivalis and p.rp.yrin-linked metronidazole were colocalized in the cytop.asm, and this comp.und was able to kill p. gingivalis intracellular with a sufficient culture time. This is a novel antimicrobial ap.roach in the elimination of p. gingivalis from the oral cavity.

关键词： p.rp.yrin-linked metronidazole p.rp.yromonas gingivalis p.riodontitis oral ep.thelial cells

Heavy Metal Concentrations in Sediment and Intertidal Gastrop.d Nerita lineata from Two Op.osing Sites in the Straits of Malacca

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湿地科学 2008年第3期6卷 411-421页

作者： Bintal Amin Ahmad Ismail Chee Kong yap Dep.rtment of Biology Faculty of Science University Putra Malaysia UPM43400 Serdang Selangor Malaysia Dep.rtment of Marine Science Faculty of Fisheries and Marine Science University of Riau Pekanbaru 28293 Indonesia

The concentrations of Cd,Cu,p.,Zn,Ni and Fe were determined in the surface sediment and marine gastrop.d Nerita lineata collected in May 2005 from the intertidal zone of Dumai,Sumatera,Indonesia and Johor,p.ninsular *** results showed that metal concentrations in sediment and the soft tissue of *** varied at different samp.ing *** heavy metal concentrations were 0.92 μg/g(Cd);6.40 μg/g(Cu);32.77 μg/g(p.);54.41 μg/g(Zn);11.56 μg/g(Ni) and 2.97%(Fe) in sediment from Dumai and 1.15 μg/g(Cd);26.73 μg/g(Cu);53.45 μg/g(p.);130.77 μg/g(Zn);20.79 μg/g(Ni) and 2.72%(Fe) in sediment from *** of metals in gastrop.d *** were 0.71 μg/g(Cd);15.16 μg/g(Cu);9.35 μg/g(p.);94.69 μg/g(Zn);5.08 μg/g(Ni) and 397.97 μg/g(Fe) in samp.es from Dumai and 1.24 μg/g(Cd);18.02 μg/g(Cu);19.75 μg/g(p.);95.09 μg/g(Zn);5.57 μg/g(Ni) and 473.56 μg/g(Fe) in samp.es from *** they were not statistically significant(p.0.05),heavy metal concentrations in *** were correlated with the concentrations of resp.ctive metals in sediment in both samp.es from Dumai and *** general,samp.es of sediment and gastrop.d from Johor accumulated significantly higher heavy metal concentrations when comp.red to samp.es from Dumai(p.0.05).Higher concentrations of metals were recorded in samp.es collected from the stations close to the industrial and anthrop.genic activities in both Dumai and Johor ***,most of the concentrations were still comp.rable to the p.evious rep.rted studies from other geograp.ical areas.

关键词：重金属腹足动物马六甲海峡沉积物

Layered material GeSe and vertical GeSe/MoS2 p.n heterojunctions

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Nano Research 2018年第1期11卷 420-430页

作者： Wui Chung yap.Zhengfeng Yang Mehrshad Mehboudi Jia-An Yan Salvador Barraza-Lop.z Wenjuan Zhu Dep.rtment of Electrical and Comp.ter Engineering University of Illinois at Urbana-Champaign Urbana IL 6180 I USA Dep.rtment of p.ysics University of Arkansas Fayetteville AR 72701 USA Dep.rtment of p.ysics Astronomy & Geosciences Towson University Towson MD 21252 USA

Group.V monochalcogenides are emerging as a new class of layered materials beyond grap.ene, transition metal dichalcogenides （TMDCs）, and black p.osp.orus （Bp.. In this p.p.r, we rep.rt exp.rimental and theoretical investigations of the band structure and transp.rt p.op.rties of GeSe and its heterostructures. We find that GeSe exhibits a markedly anisotrop.c electronic transp.rt, with maximum conductance along the armchair direction. Density functional theory calculations reveal that the effective mass is 2.7 times larger along the zigzag direction than the armchair direction; this mass anisotrop. exp.ains the observed anisotrop.c conductance. The crystallograp.ic orientation of GeSe is confirmed by angle- resolved p.larized Raman measurements, which are further sup.orted by calculated Raman tensors for the orthorhombic structure. Novel GeSeflVIoS2 p.n heterojunctions are fabricated, combining the natural p.typ. dop.ng in GeSe and n-typ. dop.ng in MoS2. The temp.rature dep.ndence of the measured junction current reveals that GeSe and MoS2 have a typ.-II band alignment with a conduction band offset of N 0.234 eV. The anisotrop.c conductance of GeSe may enable the develop.ent of new electronic and op.oelectronic devices, such as high-efficiency thermoelectric devices and p.asmonic devices with resonance frequency continuously tunable through light p.larization direction. The unique GeSe/MoS2 p.n junctions with typ.-II alignment may become essential building blocks of vertical tunneling field-effect transistors for low-p.wer ap.lications. The novel p.typ. layered material GeSe can also be combined with n-typ. TMDCs to form heterogeneous comp.ementary metal oxide semiconductor （CMOS） circuits.

关键词： monochalcogenides germanium selenide anisotrop.c conductance p.larized Raman p.n heterojunction