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L Hui-Yi WANG Tie-Shan HAN Yun-Cheng FANG Kai-Hong MENG Xuan HE Qing-Hua GUAN Xing-Cai LAN Ming-Cong 《中国物理C(英文版)》2011,35(1):26-30
The D(d,p)T reaction in Be metal environments has been measured to investigate the electron screening effect in metals in an energy region of from 5.5 keV to 10 keV in a center of mass system(CMS)at a temperature of 121 K.The depth distribution of deuteron density in Be metals has an impact on the observed reaction yields.A model of deuteron density distribution in metal has been proposed to obtain the original yields.A screening energy of(116±46)eV has been obtained with the assumed deuteron density distribution model. 相似文献
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采用机械球磨法成功制备Ag_3PO_4/MoS_2纳米片复合催化剂。运用X射线衍射仪(XRD)、透射电子显微镜(TEM)、扫描电子显微镜(SEM)、紫外可见漫反射光谱(UV-Vis)和荧光发射光谱(PL)对复合催化剂的结构和形貌进行了表征。结果表明,Ag_3PO_4纳米粒子均匀地附着在MoS_2纳米片层结构上,两者形成紧密结合。以亚甲基蓝为模拟污染物,研究复合催化剂在可见光照射下的光催化特性;通过循环实验考察复合催化剂的稳定性。结果显示,含有1%的MoS_2纳米片与Ag_3PO_4形成的复合催化剂在30 min内对亚甲基蓝的降解率为95%,其降解动力学常数是纯相Ag_3PO_4的2倍。经过5次循环实验后复合催化剂对于亚甲基蓝的降解率为84%,而纯Ag_3PO_4对于亚甲基蓝的降解率仅为35%。Ag_3PO_4/MoS_2纳米片复合催化剂具有优良的光催化活性和高稳定性,主要归因于二硫化钼纳米片与磷酸银形成异质结,磷酸银激发的电子和二硫化钼纳米片产生的空穴直接复合,从而促使光生电子从磷酸银晶体表面快速分离,减轻了磷酸银的光电子腐蚀,同时也提高了复合物的光催化活性。 相似文献
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Carriers recombination processes in charge trapping memory cell by simulation 总被引:1,自引:0,他引:1 下载免费PDF全文
We have evaluated the effects of recombination processes in a charge storage layer, either between trapped electrons and trapped holes or between trapped carriers and free carriers, on charge trapping memory cell's performances by numerical simulation. Recombination is an indispensable mechanism in charge trapping memory. It helps charge convert process between negative and positive charges in the charge storage layer during charge trapping memory programming/erasing operation. It can affect the speed of programming and erasing operations. 相似文献
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在凸性假定下,本文证明了终值型与积分型非二次判据最优调节器问题存在闭环解,由非线性状态反馈u(t)=-R-1B~*P(t,x(t))给出。反馈算子P(t,x)是拟Riccati方程的解,终值型问题的P(t,x)由一类非线性代数方程的解表出,积分型问题的P(t,x)由一类非线性Fredholm积分方程的解表出。 相似文献
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The structure of a manganese(Ⅱ) polymer,[Mn(TP)(TBZH)]2n 1(TBZH=thiabendazole,TP=terephthalic acid),has been determined by X-ray crystallography and characterized by elemental analysis,IR spectrum and thermogravimetric analysis.It crystallizes in the orthorhombic system,space group Pbcn with a=12.7813(12),b=10.7544(10),c=20.1270(19) ,V=2766.6(4)3,Z=8,C14H9Mn0.50N3O2S,Mr=310.77,Dc=1.492g/cm3,F(000)=1268,μ=0.674 mm-1 and S=1.064.The 1-D chain architecture of 1 is constructed from terephthalic acid and manganese atoms.Hydrogen bonds and aryl ring π-π stacking interactions in 1 contribute to form a 3-D supramo-lecular structure. 相似文献
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Hiroki Kanda Brian Beckford Takeji Fujibayashi Takao Fujii Yu Fujii Kenta Futatsukawa Toshiyuki Gogami Yun-Cheng Han Osamu Hashimoto Kentaro Hirose Ryotaro Honda Kenji Hosomi Alan Iguchi Takatsugu Ishikawa Yusuke Kaneko Masashi Kaneta Yuma Kasai Daisuke Kawama Taito Kawasaki Chigusa Kimura Shogo Kiyokawa Takeshi Koike Kazushige Maeda Tomofumi Maruta Nayuta Maruyama Masao Matsubara Koji Miwa Yohei Miyagi Sho Nagao Satoshi N. Nakamura Akira Okuyama Kotaku Suzuki Tadaaki Tamae Hirokazu Tamura Nobuhiro Terada Kyo Tsukada Tie-Shang Wang Fumiya Yamamoto Takeshi O. Yamamoto Hirohito Yamazaki 《Few-Body Systems》2013,54(7-10):1175-1178
Photoproduction of the neutral kaon on the deuteron has been investigated at the Research Center for Electron Photon Science, Tohoku University. We constructed the Neutral Kaon Spectrometer-2 for the detection of charged particles from the decay of the neutral kaon and the hyperon. We obtained a momentum distribution of K 0 with the inclusive measurement. It was consistent with the previous measurement. The total cross section of γ + d → K 0 + Λ + p was estimated from the measured integral cross section of γ + d → Λ + X. The total cross section with respect to the photon energy was compared with the theoretical calculations. It favored the Saclay-Lyon A model calculation with the ratio of the neutral to charged coupling constants of the axial-vector meson, K 1, as ~ ?1.5. The energy dependence and the magnitude of the total cross section were similar to the total cross section of γ + p → K + Λ. 相似文献
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Yun-Cheng Luo Ming-Kuan Wang Ling-Chao Yu Prof. Dr. Xingang Zhang 《Angewandte Chemie (International ed. in English)》2023,62(37):e202308690
The selective transition-metal catalyzed C−F bond functionalization of inexpensive industrial fluorochemicals represents one of the most attractive approaches to valuable fluorinated compounds. However, the selective C(sp2)−F bond carbofunctionalization of refrigerant hydrofluoroolefins (HFOs) remains challenging. Here, we report a nickel-catalyzed selective C(sp2)−F bond alkylation of HFO-1234yf with alkylzinc reagents. The resulting 2-trifluoromethylalkenes can serve as a versatile synthon for diversified transformations, including the anti-Markovnikov type hydroalkylation and the synthesis of bioactive molecule analogues. Mechanistic studies reveal that lithium salt is essential to promote the oxidative addition of Ni0(Ln) to the C−F bond; the less electron-rich N-based ligands, such as bipyridine and pyridine-oxazoline, feature comparable or even higher oxidative addition rates than the electron-rich phosphine ligands; the strong σ-donating phosphine ligands, such as PMe3, are detrimental to transmetallation, but the less electron-rich and bulky N-based ligands, such as pyridine-oxazoline, facilitate transmetallation and reductive elimination to form the final product. 相似文献
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The structure of a binuclear cadmium(II) quaternary complex, [Cd2(phen)2- Q2(BP)]n 1 (phen = 1,10-phenanthroline, BP = biphenyl-4,4--dicarboxylic acid, Q = 8-hydroxy- quinoline-anion), has been determined by X-ray crystallography and characterized by elemental analysis, IR spectrum and thermogravimetric analysis.It crystallizes in the monoclinic system, space group P21/n with a = 13.1906(18), b = 10.9623(15), c = 16.947(2) -, β = 111.3430(10)°, V = 2282.5(5) -3, Z = 4, Mr = 556.85, Dc = 1.620 g/cm3, F(000) = 1116, μ = 0.994 mm-1 and S = 1.056.In the structure, 1D chains are connected via biphenyl-4,4--dicarboxylic acid, 8-hydroxy quinoline anion and binuclear cadmium atoms into an infinite 1-D molecular chain architecture.Via aryl ring π-π stacking interactions a supramolecular structure is formed in 1. 相似文献