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Karst collapse is one of main important geological disasters in Linyi city of Shandong Province. In this article, risk assessment of present and forecast situation of karst collapse have been done by the method of fuzzy comprehensive evaluation based on level analysis at the first time. The hazardous assessment, the vulnerability and the expected loss have been assessed, and then the risk assessment map of karst collapse at present is obtained and prevention and control work of karst collapse is expected to develop. It puts up availability exploration on prevention of the same geohazards, and provides a reference pattern.

This paper presents a family of soliton solutions of the one-dimensional nonlinear Schrodinger equation which describes the dynamics of the dark solitons in Bose{Einstein condensates with an arbitrary x-dependent external po- tential. The obtained results show that the external potential has an important efiect on the dark soliton dynamical characteristics of the condensates. The amplitude, width, and velocity of the output soliton are relative to the source position of the external potential. The smaller the amplitude of the soliton is, the narrower its width is, and the slower the soliton propagates. The collision of two dark solitons is nearly elastic.

We consider the remote implementation of an arbitrary unitary operation on one qubit of a pure two-qubit entangled state with 100% efficiency via entanglement swapping in detail, then directly generalize this protocol from two-qubit to N-qubit entangled states. The overall classical information and distributed entanglement cost required for this quantum remote control protocol is less than the bi-directional quantum state teleportation method.

Using local operations and classical communication, we present two schemes for realizing entanglement concentration from pure entangled pairs of qutrits. These methods can be easily generalized to d-dimensional (d>3) quantum systems.

We discuss two different schemes for the probabilistic preparation of N-particle cat states using pure multiparticle entangled states via entanglement swapping and entanglement concentration. At the centre of distribution A, Alice performs all of the operations required to achieve our goal.

A scheme for teleporting a two-particle entangled state via a three-particle entangled state is proposed. It is shown that the probability of successful teleportation is twice the modulus square of the smaller Schmidt coefficient of the entangled three-particle state.

We propose an approach to measuring non-Markovianity of an open two-level system from quantum coherence perspective including l1 norm of coherence and quantum relative entropy of coherence, and derive corresponding non-Markovian conditions. Further, as a particular application, non-Markovian conditions of an open two-level system undergoing phase damping channel, random unitary channel and amplitude damping channel, respectively are investigated. Specifically speaking, for the three channels we obtain non-Markovian conditions based on l1 norm of coherence at any initial state of system, and find that non-Markovian conditions are the same as the conditions of other measurements, i.e., information back-flow, divisibility and quantum mutual entropy for the phase damping channel and amplitude damping channel, but non-Markovian conditions new and different from the conditions of other measurements for random unitary channel. On the other hand, for phase damping channel we obtain non-Markovian conditions based on quantum relative entropy of coherence at any initial state of system, which are the same as the conditions of other measures, i.e., information back-flow, divisibility and quantum mutual entropy. However, for the random unitary channel and amplitude damping channel we obtain non-Markovian conditions at maximally coherent state of system.

By using the first-principles calculation based on density functional theory, we propose some approaches to improving the efficiency for the photocatalyst Ag2ZnSnS4 from a theoretical aspect. Comparing its band edge positions with those of other similar compounds, we find that Cu, Ge codoping can adjust both the band gaps and band edge positions of Ag2ZnSnS4 at the same time, which can optimize its band structure for water splitting. In addition, Ag2ZnSnS4 has a type-Ⅱ band offset with another photocatalyst CuGaSe2. Preparation of its homojunction can also improve their efficiencies of photocatalysis hydrolyzation.

By using a multiple-scale method, we analytically study the effect of a localized impurity on the soliton dynamics in the Bose-Einstein condensates. It is shown that a dark soliton can be transmitted through a repulsive (or attractive) impurity, while at the position of the localized impurity the soliton can be quasitrapped by the impurity. Additionally, we find that the strength of the localized impurity has an important effect on the dark soliton dynamics. With increasing strength of the localized impurity, the amplitude of the dark soliton becomes bigger, while its width is narrower, and the soliton propagates slower.