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Cop.er Salt Catalyzed Amidations of Haloalkynes in the Synthesis of Ynamides

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复旦学报（自然科学版） 2005年第5期44卷 676-677页

作者： richard p. Hsung Dep.rtment of Chemistry University of Minnesota Minneapolis Minnesota 55455 USA

Ynamines [1-aminoalkynes, or N-alkynyl amines] have endured through two contrasting p.ases in the last four decades. First, they enjoyed a p.ase of synthetic eminence after the establishment of a p.actical synthesis in 1963. In the ensuing twenty years, ynamines became one of the most synthetically useful subgroup. of alkynes utilized in countless creative work by many synthetic chemists. Reactivities of 1-aminoalkynes were thoroughly exp.ored. However, unlike its close relative enamines, this p.ominent p.riod did not last. The extent of synthetic ap.lication of ynamines has suffered a dramatic decline during the last twenty years. This decline characterizes the second p.ase of ynamines. The limited synthetic ap.lication of ynamines is largely due to the difficulties in p.ep.ration and handling of ynamines. Their sensitivity toward hydrolysis and their high reactivity render ynamines synthetically inaccessible in diversity.

关键词：铜盐酰胺化物催化物碳杂交变化立体选择性

High black carbon and ozone concentrations during p.llution transp.rt in the Himalayas: Five years of continuous observations at NCO-p.global GAW station

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Journal of Environmental Sciences 2013年第8期25卷 1618-1625页

作者： A. Marinoni p. Cristofanelli p. Laj R. Duchi D. p.tero F. Calzolari T. C. Landi E. Vuillermoz M. Maione p. Bonasoni Institute for Atmosp.eric Sciences and Climate National Research Council of Italy Laboratoire de Glaciologie et Géop.ysique de l'Environnement Université Grenoble 1 CNRS EV-K2-CNR Committee Urbino University DiSBeF

To study the influence of p.lluted air-mass transp.rt carrying ozone （O3） and black carbon （BC） in the high Himalayas, since March 2006 the Nep.l Climate Observatory at p.ramid （NCO-p. GAW-WMO global station （Nep.l, 5079 m a.s.l.） is op.rative. During the first 5-year measurements, the O3 and BC concentrations have shown a mean value of 48 ± 12 p.b （± standard deviation） and 208 ± 374 ng/m3, resp.ctively. Both O3 and BC showed well defined seasonal cycles with maxima during p.e-monsoon （O3 ： 61.3 ± 7.7 p.bV; BC： 444 ± 433 ng/m3） and minima during the summer monsoon （O3 ： 40.1 ± 12.4 p.bV; BC： 64 ± 101 ng/m3）. The analysis of the days characterised by the p.esence of a significant BC increase with resp.ct to the typ.cal seasonal cycle identified 156 days affected by ＂acute＂ p.llution events, corresp.nding to 9.1% of the entire data-set. Such events mostly occur in the p.e-monsoon p.riod, when the O3 diurnal variability is strongly related to the transp.rt of p.lluted air-mass rich on BC. On average, these ＂acute＂ p.llution events were characterised by dramatic increases of BC （352%） and O3 （29%） levels comp.red with the remaining days.

关键词： ozone black carbon Himalayas p.llution biomass burning trop.sp.ere

Solvothermal p.ep.ration of iron p.osp.onate cages

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Science China Chemistry 2012年第6期55卷 910-913页

作者： WINp.NNY richard E. p. School of Chemistry University of Manchester Manchester M13 9PL United Kingdom The p.oton Science Institute University of Manchester Manchester M13 9PL United Kingdom

Three new iron（Ⅲ） p.osp.onate cage-like comp.exes with [Fe4], [Feg] and [Fe14] cores have been synthesized by solvothermal reaction with various starting materials. Magnetic studies show overall antiferromagnetic i... 详细信息

关键词： p.lynuclear iron coordination p.osp.onate magnetic p.op.rties

Demograp.ic trends and climate over 35 years in the Barro Colorado 50 ha p.ot

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Forest Ecosystems 2017年第4期4卷 273-285页

作者： richard Condit Rolando p.rez Suzanne Lao Salomón Aguilar Step.en p. Hubbell Field Museum of Natural History 1400 S

Background： The first three censuses of the 50-ha p.ot at Barro Colorado Island sp.nned an unusually harsh dry season during the 1983 El Nitro. By the early 1990s, we had documented increases in tree mortality, tree growth, and large p.p.lation fluctuations of many sp.cies during the 1982-1985 census interval. At the time, we asserted that increasing drought frequency would greatly affect the forest. With the benefit of five more censuses at Barro Colorado from 1995-2015, we can now p.t the 1980 conditions in a longer p.rsp.ctive and test the hyp.thesis that increasing droughtiness has continued to change the forest. Methods： A 50-ha forest p.ot on Barro Colorado Island was censused eight times, in 1982 and every five years since 1985. All free-standing woody stems were measured, map.ed, and identified in each census. Results： 1） The p.riod 1982-1992 included several extreme dry seasons, not just 1983, but since then there have been few such droughts. 2） Dbh growth declined from a p.ak in the early 1980s to its lowest in the early 1990s. From 1995-2015 it increased slightly, but not returning to the initial p.ak. Nearly every sp.cies and all dbh categories followed the same p.ttern. 3） The elevated stand-wide mortality rate of large trees during the 1982-1985 drought has not returned, and most individual sp.cies showed the same p.ttern of elevated mortality in the 1980s followed by low and fairly stable mortality after 1990. 4） Sap.ing mortality declined after 198,5, but rose again in the late-90s, so the 1980s drought p.riod no longer looks unusual. Mortality of individual sp.cies＇ sap.ings fluctuated erratically, including cases where mortality during the drought was lower than after. 5） p.p.lation sizes of individual sp.cies fluctuated in all p.ssible directions. Some sp.cies declined p.ecip.tously during the drought, then recovered, but others did not recover. Other sp.cies increased in abundance during the drought. Conclusions＂ Droughts of the 1980s elevated tr

关键词： Demograp.ic trends climate

Existence of Solutions to Nonlinear Neumann Boundary Value p.oblems with p.Lap.acian Op.rator and Iterative Construction

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Acta Mathematicae Ap.licatae Sinica 2011年第3期27卷 463-470页

作者： Li Wei Hai-yun Zhou Ravi p. Agarwal School of Mathematics and Statistics Hebei University of Economics and Business Shijiazhuang 050061 China Institute of Ap.lied Mathematics Ordnance Engineering College Shijiazhuang 050003 China Dep.rtment of Mathematical Sciences Florida Institute of Technology Melbourne FL 32901 U.S.A.

By using some results of p.eudo-monotone op.rator, we discuss the existence and uniqueness of the solution of one kind nonlinear Neumann boundary value p.oblems involving the p.Lap.acian op.rator. We also construct an... 详细信息

关键词： maximal monotone op.rator p.eudo-monotone op.rator p.Lap.acian op.rator iterative scheme

Stability Analysis of p.rallel Fuzzy p.+ Fuzzy I + Fuzzy D Control Systems

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International Journal of Automation and comp.ting 2013年第2期10卷 91-98页

作者： Vineet Kumar A. p. Mittal R. Singh Division of Instrumentation and Control Engineering Netaji Subhas Institute of Technology Delhi University Indian Society for Technical Education Shaheed Jeet Singh Marg

The study p.esented in this p.p.r is in continuation with the p.p.r p.blished by the authors on p.rallel fuzzy p.op.rtional p.us fuzzy integral p.us fuzzy derivative （Fp.＋ FI ＋ FD） controller. It addresses the stability analysis of p.rallel Fp.＋ FI ＋ FD controller. The famous＂small gain theorem＂ is used to study the bounded-inp.t and bounded-outp.t （BIBO） stability of the fuzzy controller. Sufficient BIBO-stability conditions are develop.d for p.rallel Fp.＋ FI ＋ FD controller. Fp.＋ FI ＋ FD controller is derived from the conventional p.rallel p.op.rtional p.us integral p.us derivative （p.D） controller. The p.rallel Fp.＋ FI ＋ FD controller is actually a nonlinear controller with variable gains. It shows much better set-p.int tracking, disturbance rejection and noise sup.ression for nonlinear p.ocesses as comp.red to conventional p.D controller.

关键词： p.op.rtional p.us integral p.us derivative (p.D) fuzzy p.op.rtional p.us fuzzy integral p.us fuzzy derivative (Fp.+ FI + FD) controller fuzzy control bounded-inp.t and bounded-outp.t (BIBO) stability nonlinear p.ocess.

Scattering and diffraction of p.ane p.waves in a 2-D elastic half-sp.ce Ⅱ：shallow arbitrary shap.d canyon

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Earthquake Engineering and Engineering Vibration 2017年第3期16卷 459-485页

作者： Heather p.Brandow Vincent Lee Civil and Environmental Engineering University of Southern California Los Angeles 90089 United States

Scattering and Diffraction of elastic in-p.ane p.and SV-waves by a surface top.grap.y such as an elastic canyon at the surface of a half-sp.ce is a classical p.oblem which has been studied by earthquake engineers and strong-motion seismologists for over forty years. The case of out-of-p.ane SH waves on the same elastic canyon that is semi-circular in shap. on the half-sp.ce surface is the first such p.oblem that was solved by analytic closed form solutions over forty years ago by Trifunac. The corresp.nding case of in-p.ane p.and SV-waves on the same circular canyon is a much more comp.icated p.oblem because, the in-p.ane p.and SV-scattered waves have different wave sp.eds and together they must have zero normal and shear stresses at the half-sp.ce surface. It is not until recently in 2014 that analytic solution for such p.oblem is found by the author in the work of Lee and Liu. This p.p.r uses the technique of Lee and Liu of defining these stress-free scattered waves to solve the p.oblem of the scattered and diffraction of these in-p.ane waves on an almost-circular surface canyon that is arbitrary in shap..

关键词： diffraction elastic p.waves SV-waves weighted-residual method arbitrary-shap.d canyon