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131.
132.
G. Grawert 《Zeitschrift für Physik A Hadrons and Nuclei》1994,348(4):293-300
Experimental results of the 1st rank analyzing power for elastic scattering of6Li and7Li could be only understood when including coupling to inelastic channels in the calculations. This finding — established for some time — yet presents some open questions regarding the energy dependence of the spin and polarization effects. Semiclassical calculations presented here might clarify the relevant physical background of the earlier quantummechanically exact results. 相似文献
133.
Yanwei Zhu Wenfang Deng Yueming Tan Jianqiao Shi Jingcheng Wu Wenbo Lu Jianfeng Jia Shuangyin Wang Yuqin Zou 《Advanced functional materials》2023,33(45):2304985
Photocatalytic selective oxidation of 5-hydroxymethylfurfural (HMF) coupled H2 production offers a promising approach to producing valuable chemicals. Herein, an efficient in situ topological transformation tactic is developed for producing porous O-doped ZnIn2S4 nanosheets for HMF oxidation cooperative with H2 evolution. Aberration-corrected high-angle annular dark-field scanning TEM images show that the hierarchical porous O-ZIS-120 possesses abundant atomic scale edge steps and lattice defects, which is beneficial for electron accumulation and molecule adsorption. The optimal catalyst (O-ZIS-120) exhibits remarkable performance with 2,5-diformylfuran (DFF) yields of 1624 µmol h−1 g−1 and the selectivity of >97%, simultaneously with the H2 evolution rate of 1522 µmol h−1 g−1. Mechanistic investigations through theoretical calculations show that O in the O-ZIS-120 lattice can reduce the oxidation energy barrier of hydroxyl groups of HMF. In situ attenuated total reflection surface-enhanced infrared absorption spectroscopy (ATR-SEIRAS) results reveal that DFF* (C4H2(CHO)2O*) intermediate has a weak interaction with O-ZIS-120 and desorb as the final product. This study elucidates the topotactic structural transitions of 2D materials simultaneously with electronic structure modulation for efficient photocatalytic DFF production. 相似文献
134.
The simultaneous engineering of sulfur cathode and Li anode is critical for electrolyte-starved high energy density Li–S batteries, in which slow electrochemical conversions and side chemical reactions of dead sulfur are found to be the determining factors in limiting the sulfur utilization, corresponding to the poor reversible capacity of Li–S batteries. Herein, this work challenges the conventional wisdom of heterogeneous and homogeneous catalyses in Li–S batteries and proposes the concept of integrated–heterogeneous catalysis to simultaneously scavenge the dead sulfur and dead lithium to compensate the active materials sulfur and lithium loss simply through adding a small amount of ZnI2 into conventional electrolyte of Li–S cells. Regulated by integrated–heterogeneous catalysis, over 1300 h of cycling is realized in Li||Li symmetric cells, revealing superb compatibility of the ZnI2-incorporated electrolyte with lithium metal. Meanwhile, the ZnI2 shows good prospects in promoting the reutilization of dead sulfur in both theoretical calculation and experimental tests. Practically, a high initial capacity of 1170 mAh g−1 with decent cycling stability is achieved in electrolyte-starved and high-loading pouch cells (5.0 µL mg−1 and 5.2 mg cm−2). 相似文献
135.
Xiangyu Meng Yuzhao Liu Le Yu Jieshan Qiu Zhiyu Wang 《Advanced functional materials》2023,33(11):2211062
Anode-free batteries can maximize the energy density but their development is hindered by a lack of Li-rich cathodes for compensating the irreversible Li loss. Li2S cathode is particularly appealing to this desire due to 2.6–4.7 folds more Li content and 4.2–6.8 times higher capacity than conventional intercalation cathodes. But its practical application is hindered by poor stability against moisture attacking in the air. Herein, a facile expendable polymer sheathing strategy toward air-stable Li2S cathodes with high capacities for developing high-performance quasi-solid-state anode-free batteries without risk of cell leakage is reported. Tight protection by dense polymer barrier dramatically prolongs the lifetime of Li2S cathode by 2,000 times at least in the air. Such air-stable Li2S cathode allows for high compatibility of anode-free battery production with commercial schemes. More attractively, the polymer protective layer can in situ transform to multifunctional gel polymer electrolyte for releasing ionic pathways and enhancing cell performance by inhibiting LiPS loss and smoothing Li plating. With air-stable Li2S cathode, the quasi-solid-state anode-free cells are assembled in ambient environment to deliver superb volumetric energy density of 1093 Wh L−1. This study may shed new light to push the commercialization of high-energy and reliable anode-free batteries forward. 相似文献
136.
Jiafeng Zhu Qingyuan Bi Yinghao Tao Wenyao Guo Jinchen Fan Yulin Min Guisheng Li 《Advanced functional materials》2023,33(15):2213131
Designing and developing visible-light-responsive materials for solar to chemical energy is an efficient and promising approach to green and sustainable carbon-neutral energy systems. Herein, a facile in situ growth hydrothermal strategy using Mo-modified ZnIn2S4 (Mo-ZIS) nanosheets coupled with NiTiO3 (NTO) microrods to synthesize multifunctional Mo-modified ZIS wrapped NTO microrods (Mo-ZIS@NTO) photocatalyst with enhanced interfacial electric field (IEF) effect and typical S-scheme heterojunction is reported. Mo-ZIS@NTO catalyst possesses wide-spectrum light absorption properties, excellent visible light-to-thermal energy effect, electron mobility, charges transfer, and strong IEF and exhibits excellent solar-to-chemical energy conversion for efficient visible-light-driven photocatalytic hydrogen evolution. Notably, the engineered Mo1.4-ZIS@NTO catalyst exhibits superior performance with H2 evolution rate of up to 14.06 mmol g−1 h− 1 and the apparent quantum efficiency of 44.1% at 420 nm. The scientific explorations provide an in-depth understanding of microstructure, S-scheme heterojunction, enhanced IEF, Mo-dopant facilitation effect. Moreover, the theoretical simulations verify the critical role of Mo element in promoting the adsorption and activation of H2O molecules, modulating the H adsorption behavior on active S sites, and thus accelerating the overall catalytic efficiency. The photocatalytic hydrogen evolution mechanism via S-scheme heterojunction with adjustable IEF regulation over Mo1.4-ZIS@NTO is also demonstrated. 相似文献
137.
Erik G. F. Thomas 《Acta Appl Math》1996,43(2):191-232
We construct an analogue of the Feynman path integral for the case of % MathType!MTEF!2!1!+-% feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr% 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9% vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x% fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaeyOeI0YaaS% aaaeaacaaIXaaabaGaamyAaaaadaWcaaqaaiabgkGi2cqaaiabgkGi% 2kaadshaaaqeduuDJXwAKbYu51MyVXgaiuaacqWFvpGAcaWG0bGaey% ypa0JaamisamaaBaaaleaacaGGOaaabeaakmaaBaaaleaacaGGPaaa% beaakiab-v9aQjaadshaaaa!4A8D!\[ - \frac{1}{i}\frac{\partial }{{\partial t}}\varphi t = H_( _) \varphi t\] in which H
() is a self-adjoint operator in the space L
2(M)= % MathType!MTEF!2!1!+-% feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr% 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9% vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x% fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaeSOaHmkaaa!3744!\[\mathbb{C}\], where
M
is a finite set, the paths being functions of % MathType!MTEF!2!1!+-% feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr% 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9% vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x% fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaeSyhHekaaa!375D!\[\mathbb{R}\] with values in M. The path integral is a family of measures F
t,t with values in the operators on L
2(M), or equivalently, a family of complex measures corresponding to matrix coefficients.It is shown that these measures on path space are in some sense dominated by the measure of a Markov process. This implies that F
t,t is concentrated on the set of step functions S[t,t].This allows one to make sense of, and prove, the analogue of Feynman's formula for the propagator of the Hamiltonian H=H
0+V, where V is a potential, namely the formula: % MathType!MTEF!2!1!+-% feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr% 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9% vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x% fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaaeyzamaaCa% aaleqabaGaeyOeI0IaamyAaiaacIcacaWG0bGaai4jaiabgkHiTiaa% dshacaGGPaGaamisaaaakiabg2da9maapebabaGaaeyzamaaCaaale% qabaGaeyOeI0IaamyAamaapedabaGaamOvaiaacIcatCvAUfKttLea% ryqr1ngBPrgaiuGacqWF4baEcaGGOaGaam4CaiaacMcacaGGPaGaae% izaiaabohaaWqaaiaadshaaeaacaWG0bGaai4jaaGdcqGHRiI8aaaa% kiaadAeadaWgaaWcbaGaamiDaiaacEcacaGGSaGaamiDaaqabaGcca% GGOaGaaeizaiab-Hha4jaacMcaaSqaaiaadofacaGGBbGaamiDaiaa% cYcacaWG0bGaai4jaiaac2faaeqaniabgUIiYdaaaa!6410!\[{\text{e}}^{ - i(t' - t)H} = \int_{S[t,t']} {{\text{e}}^{ - i\int_t^{t'} {V(x(s)){\text{ds}}} } F_{t',t} ({\text{d}}x)} \]and the corresponding formulas for the matrix coefficients, in which the integral extends over the paths beginning and ending in the appropriate points. We show that the measures F
t,t are completely determined by these equations and by a certain multiplicative property.The path integral corresponding to a two-particle system without interaction is the direct product of the corresponding path integrals. The propagator for a two-particle system with interaction can be obtained by repeated integration.Finally, we show that the above integral formula can be generalized to the case where the potential is time dependent. 相似文献
138.
David Applebaum 《Letters in Mathematical Physics》1993,28(3):231-237
The index of a Fredholm operator associated to a-summable Fredholm module is expressed in terms of the vacuum expectation value of a unitary operator-valued stochastic process which satisfies a stochastic differential equation with unbounded coefficients driven by fermion noise. 相似文献
139.
Yu. A. Berezhnoy I. N. Kudryavtsev A. P. Soznik 《Zeitschrift für Physik A Hadrons and Nuclei》1993,344(4):431-438
The experimental data on the 180 MeV proton and 50, 180 MeV antiproton scattering by the nuclei12C,40Ca and208Pb have been analysed on the basis of the phenomenological diffraction theory. The optical properties of the nuclei with regards to the incident protons and antiprotons are investigated. Various limiting cases of the proton- and antiproton-nucleus scattering are considered. The contribution of the Coulomb and the spin-orbit interactions to the differential cross sections of these processes has been also analysed.The authors are indebted to D.M. Skrypnik for assistance in preparing the English version of this paper. 相似文献
140.
M. A. Natsheh 《Periodica Mathematica Hungarica》1993,26(1):7-14
Leth be a cyclic action of periodn onM, whereM is eitherS
1×K, K is the Klein bottle or on
, the twisted Klein bottle bundle overS
1, such that there is a fiberingq:MS
1 with fiber a Klein bottleK or a torusT with respect to which the action is fiber preserving. We classify all such actions and show that they might be distinguished by their fixed points or by their orbit spaces. 相似文献