等离激元光催化研究进展

近年来,等离激元光催化剂因其优异的可见光吸收性和光催化活性,成为光催化治理环境、纳米材料合成和半导体优化等学科领域的研究热点和重点之一。本文在对纳米贵金属参与光催化过程的等离激元光催化剂机理和光催化活性提高机理等光催化原理进行分析的基础上,对等离激元光催化剂进行分类探讨并阐述了等离激元光催化剂的合成方法,按照光催化剂的组成将等离激元光催化剂分为Ag@AgX(X=Cl/Br/I)等离激元光催化剂、贵金属/半导体等离子光催化剂等,最后对等离激元光催化剂在环境净化和能源利用等领域的原理和应用(废水处理、光解水制氢、CO_(2)还原、抗菌和空气净化等)进行综述,并对等离激元光催化剂未来发展进行展望。

Cognitive-behavioural therapy for personal recovery of patients with schizophrenia:A systematic review and meta-analysis

Background To date, cognitive-behavioural therapy (CBT) trials have primarily focused on clinical recovery;however, personal recovery is actually the fundamental aspect of the recovery process. The aim of this study was to summarise and synthesise the existing evidence regarding the effectiveness of CBT for personal recovery In patients with schizophrenia. Aim This study aimed to determine the effectiveness of CBT for personal recovery in patients with schizophrenia. Methods A systematic search of the literature in PsycINFO, PubMed, Cochrane (CENTRAL), Embase and Web of Science (SCI) was conducted to identify randomised controlled trials reporting the impact of CBT interventions on personal recovery in patients with schizophrenia. The estimated effect sizes of the main study outcomes were calculated to estimate the magnitude of the treatment effects of CBT on personal recovery. We also evaluated the CBT’s effect size at the end-of-treatment and long-term (follow-up) changes in some aspects of personal recovery. Results Twenty-five studies were included in the analysis. The effect of CBT on personal recovery was 2.27 (95% CI 0.10 to 4.45;I^2=0%;p=0.04) at post-treatment and the long-term effect size was 2.62 (95% CI 0.51 to 4.47;I^2=0%;p=0.02). During the post-treatment period, the pooled effect size of CBT was 0.01 (95% CI -0.12 to 0.15;I^2=33.0%;p>0.05) for quality of life (QoL), 0.643 (95% CI 0.056 to 1.130;I^2=30.8%;p<0.01) for psychological health-related QoL,-1.77 (95% CI -3.29 to -0.25;I^2=40%;p=0.02) for hopelessness and 1.85 (95% CI 0.69 to 3.01;I^2=41%;p<0.01) for self-esteem. We also summarised the effects of CBT on QoL (subscale scores not included in the evaluation of the pooled effect size), self-confidence and connectedness, and all results corresponded to positive effects. However, there was insufficient evidence regarding the long-term effects of CBT on personal recovery. Conclusions CBT is an effective therapy with meaningful clinical effect sizes on personal recovery and some aspects of personal recovery of schizophrenia after treatment. However, the effect is relatively immediate and rapidly decreases as time progresses. Therefore, in the future, more studies should focus on the mechanism of CBT for personal recovery and the factors that influence the long-term effects of CBT.

Eliminating Outdated Capacity to Promote Energy Conservation in China’s Coal-Fired Power Industry

1. Introduction As China’s main power source, the coal-fired power industry has supplied about 80% of electricity in China over the past several decadesy, while consuming roughly half of the coal generated in China [1]. Given China’s resources endowment [2], it will be difficult to change the dominant status of coal in China’s primary energy structure in the near future [3].

Three-dimensional oxygen-doped porous graphene:Sodium chloridetemplate preparation,structural characterization and supercapacitor performances

Supercapacitor is a new type of energy storage device,which has the advantages of high-power property and long cycle life.In this study,three-dimensional graphene(3 D-GN)with oxygen doping and porous structure was prepared from graphene oxide(GO)by an inexpensive sodium chloride(NaCl)template,as a promising electrode material for the supercapacitor.The structure,morphology,specific surface area,pore size,of the sample were characterized by XRD,SEM,TEM and BET techniques.The electrochemical performances of the sample were tested by CV and CDC techniques.The 3 D-GE product is a threedimensional nano material with hierarchical porous structures,its specific surface area is much larger than that of routine stacked graphene(GN),and it contains a large number of mesoporous and macropores,a small amount of micropores.The capacitance characteristics of the 3 D-GN electrode material are excellent,showing high specific capacitance(173.5 F·g^(-1)at 1 A·g^(-1)),good rate performance(109.2 F·g^(-1)at 8 A·g^(-1))and long cycle life(88%capacitance retention after 10,000 cycles at 8 A·g^(-1))

Polarization-resolved Raman spectra of α-PtO_(2)

Using density functional theory,we investigate the vibrational properties and polarization-resolved Raman spectra ofα-PtO_(2) and obtain the Raman tensor and angle-dependent Raman intensity of α-PtO_(2).It is found that the polar plot of A_(1g)mode in parallel polarization configuration is useful in identifying the orientation of the crystal.The Raman intensity of the E_(g) mode is about five times stronger than that of the A_(1g) mode.The Raman intensity is about three times stronger when the wave vector of the incident light is in x or y direction than in z direction.Our work will help the material scientists to characterize the α-PtO_(2) and to identify its orientation by comparing the experimental spectra with our result.

Gas-phase synthesis of Ti_(2)CCl_(2) enables an efficient catalyst for lithiumsulfur batteries

MXenes have aroused intensive enthusiasm because of their exotic properties and promising applications.However,to date,they are usually synthesized by etching technologies.Developing synthetic technologies provides more opportunities for innovation and may extend unexplored applications.Here,we report a bottom-up gas-phase synthesis of Cl-terminated MXene(Ti_(2)CCl_(2)).The gas-phase synthesis endows Ti_(2)CCl_(2) with unique surface chemistry,high phase purity,and excellent metallic conductivity,which can be used to accelerate polysulfide conversion kinetics and dramatically prolong the cyclability of Li-S batteries.In-depth mechanistic analysis deciphers the origin of the formation of Ti_(2)CCl_(2) and offers a paradigm for tuning MXene chemical vapor deposition.In brief,the gas-phase synthesis transforms the synthesis of MXenes and unlocks the hardly achieved potentials of MXenes.

旋转导向钻井工具装备的微小故障检测

旋转导向钻井系统是油气开发领域的高端装备,其核心部分——动态指向式旋转导向钻井工具的可靠运行是钻井系统正常工作的重要前提.本文基于模型的方法研究了导向钻井工具装备的微小故障检测,有望为系统的运行维护与健康管理提供重要保障.首先,基于机理建模方法得到了导向钻井工具装备的数学模型.然后,利用移动加权平均方法提高了残差对微小故障的敏感性.基于非中心χ^(2)分布的性质,实现了对微小故障在统计意义下的可检测性分析,得到了保证误报率与漏报率在允许范围内的窗口长度和权值.最后,在旋转导向钻井工具原理样机上进行实验,实验结果验证了所提方法的有效性.

Review of Key Problems Related to Integrated Energy Distribution Systems

Integrated energy distribution system(IEDS)is one of the integrated energy and power system forms,which involves electricity/gas/cold/heat and other various energy forms.The energy coupling relationship is close and complex.IEDS is the focus of regional energy internet research and development at home and abroad.Compared with the traditional power distribution system,IEDS through the multi-energy coupling link comprehensive utilization,effectively improve the distribution system economy,safety,reliability,flexibility and toughness,but also to ease the regional energy system environmental pressure.IEDS is an important direction for the future development of energy systems,and its related research and practice on China’s energy system development also has important practical and strategic significance.This paper summarizes the related researches of the IEDS and explores the energy operation characteristics and coupling mechanisms.What’s more,the integrated model of IEDS is summarized.On these bases,this paper discusses and prospects some key issues such as joint planning,optimization control and security analysis,state estimation and situational awareness and generalized demand side management.

An overview of the development history and technical progress of China's coal-fired power industry

As the main power source of China, coalfired power industry has achieved a great progress in installed capacity, manufacturing technologies, thermal efficiency, as well as pollutant control during the past century. With the fast development of renewable energies, coal-fired power industry is experiencing a strategic transformation. To specify the development of coal-fired power industry, its development history is reviewed and the technical progresses on aspects of thermal efficiency, pollutants control and peaking shaving capacity are discussed. It is concluded that the role of China's coal-fired power source would be transformed from the dominant position to a base position in power source structure. Considering the sustainable development of coal-fired power industry in energy conservation, emission control, and utilization of renewable energies, it is suggested that the national average thermal efficiency should be improved by continual up-gradation of units by using advanced technologies and eliminating outdated capacity. Moreover, the emission standard of air pollutants should not be stricter any more in coal-fired power industry. Furthermore, the huge amount of combined heat and power (CHP) coal-fired units should be operated in a decoupled way, so as to release more than 350 GW regulation capacity for the grid to accept more renewable energy power.

Identification of Graves’ophthalmology by laser-induced breakdown spectroscopy combined with machine learning method

Diagnosis of the Graves’ophthalmology remains a significant challenge.We identified between Graves’ophthalmology tissues and healthy controls by using laser-induced breakdown spectroscopy(LIBS)combined with machine learning method.In this work,the paraffin-embedded samples of the Graves’ophthalmology were prepared for LIBS spectra acquisition.The metallic elements(Na,K,Al,Ca),non-metallic element(O)and molecular bands((C-N),(C-O))were selected for diagnosing Graves’ophthalmology.The selected spectral lines were inputted into the supervised classification methods including linear discriminant analysis(LDA),support vector machine(SVM),k-nearest neighbor(ANN),and generalized regression neural network(GRNN),respectively.The results showed that the predicted accuracy rates of LDA,SVM,ANN,GRNN were 76.33%,96.28%,96.56%,and 96.33%,respectively.The sensitivity of four models were 75.89%,93.78%,96.78%,and 96.67%,respectively.The specificity of four models were 76.78%,98.78%,96.33%,and 96.00%,respectively.This demonstrated that LIBS assisted with a nonlinear model can be used to identify Graves’ophthalmopathy with a higher rate of accuracy.The ANN had the best performance by comparing the three nonlinear models.Therefore,LIBS combined with machine learning method can be an effective way to discriminate Graves’ophthalmology.

Air pollutant control and strategy in coal-fired power industry for promotion of China’s emission reduction

Coal-fired power industry has always been the major power source in China. As coal-fired power industry consumes around a half of China’s coal production, it is always thought to be a big air pollutant emission source. As more and more strict legislations in coal-fired power industry have been issued by the government, the emission performance in coal-fired power industry has been drastically reduced recently.Based on a brief review of the development of emission control in China’s coal-fired power industry, the affecting mechanism among the development of installed capacities of emission control device, pollutant emission, and emission performances in coal-fired power industry is studied. According to a systematic study on the development of emissions of classified categories, the role of coal-fired power industry as a pollutant source is reevaluated.It is found that, coal- fired power industry has contributed the most to China5S emission reduction, and the barycenter of air pollutant emission has been transformed to other high energy consumption industries,like heat, iron/steel, and cement.Then some development strategies are suggested, such as maintaining the current emission standard in coal-fired power industry;expending the coal-fired power emission standards to categories of heat generation and supply, nonmetallic mineral production and ferrous metals smelt-ing and processing;and controlling other heavy metal by consulting the method of Hg control.

Experimental Investigation of Dimensionless Velocity and Shearing Stress in Boundary Layer Flow on Continuous Moving Surface in Power Law Fluids

An analysis is carried out to study the steady flow characteristics from a continuous flat surface moving in a parallel free stream of non-Newtonian power law fluid. The constitutive equations of the fluid are transformed into dimensionless ones. The velocity field is measured by Particle Image Velocimetry. Experimental results are obtained for the distribution of velocity. The influence of wall velocity ratio parameter on boundary layer flow field is observed in the experiment. Dimensionless velocity distribution and shearing stress distribution are obtained by post-processing experimental results. The effects of various physical parameters like velocity ratio parameter and similarity variable on various momentum transfer characteristics are discussed in detail and shown graphically. It is indicated that dimensionless velocity increases with velocity ratio parameter and similarity variable, and that dimensionless shearing stress decreases with velocity ratio parameter and similarity variable.

Energy conservation in China's coal-fired power industry by installing advanced units and organized phasing out backward production

Coal-fired power is the main power source and the biggest contributor to energy conservation in the past several decades in China.It is generally believed that advanced technology should be counted on for energy conservation.However,a review of the decline in the national average net coal consumption rate(NCCR)of China's coal-fired power industry along with its development over the past few decades indicates that the upgradation of the national unit capacity structure(including installing advanced production and phasing out backward production)plays a more important role.A quantitative study on the effect of the unit capacity structure upgradation on the decline in the national average NCCR suggests that phasing out backward production is the leading factor for the decline in the NCCR in the past decade,followed by the new installation,whose sum contributes to approximately 80%of the decline in the national average NCCR.The new installation has an effective affecting period of about 8 years,during which it would gradually decline from a relatively high value.Since the effect of phasing out backward production may remain at a certain degree given a continual action of phasing out backward capacity,it is suggested that the organized action of phasing out backward production should be insisted on.

A decoupled method to identify affecting mechanism of crosswind on performance of a natural draft dry cooling tower

The natural draft dry cooling tower(NDDCT)has been increasingly used for cooling in power generation in arid area.As crosswind affects the performance of a NDDCT in a complicated way,and the basic affecting mechanism is unclear,attempts have been made to improve the performance of a NDDCT based on limited experiences.This paper introduces a decoupled method to study the complicated crosswind effects on the inlet and outlet of a NDDCT separately by computational fluid dynamics(CFD)modeling and hot state experiments.Accordingly,the basic affecting mechanism of crosswind on the NDDCT performance is identified.Crosswind changes the inlet flow field of a NDDCT and induces mainstream vortices inside the tower,so as to degrade the ventilation.Besides,low crosswind deflects the upward plume at the outlet to further degrade the ventilation,while high crosswind induces the low pressure area at the outlet to reduce the ventilation degradation.

Magnetism variation of the compressed antiferromagnetic topological insulator EuSn_(2)As_(2)

We report a comprehensive high-pressure study,up to 21.1 GPa,on the antiferromagnetic topological insulator EuSn_(2)As_(2) achieved through synchrotron X-ray diffraction,Raman scattering,electrical resistance,magnetic resistance,and Hall transport measurements in combination with first-principles calculations.The Néel temperatures determined from resistance are increased from(24±1)to(77±8)K under pressure,which is a result of enhanced magnetic exchange couplings between Eu^(2+) ions yielded by our first-principles calculations.The negative magnetoresistance of EuSn_(2)As_(2) persists to higher temperatures accordingly.However,the enhancement of the observed Néel temperatures deviates from the calculations above 10.0 GPa.In addition,the magnitude of the magnetoresistance,Hall coefficients,and charge carrier densities show abrupt changes between 6.9 and 10.0 GPa.The abrupt changes likely originate from a pressure-induced valence change of Eu ions from a divalent state to a divalent and trivalent mixed state or are related to the structural transition revealed by Raman scattering measurements.Our results provide insight into magnetism variation in EuSn_(2)As_(2) and similar antiferromagnetic topological insulators under pressure.

Optimal binary codes and binary construction of quantum codes

This paper discusses optimal binary codes and pure binary quantum codes created using Steane construction. First, a local search algorithm for a special subclass of quasi-cyclic codes is proposed, then five binary quasi-cyclic codes are built. Second, three classical construction methods are generalized for new codes from old such that they are suitable for constructing binary self-orthogonal codes, and 62 binary codes and six subcode chains of obtained self-orthogonal codes are designed. Third, six pure binary quantum codes are constructed from the code pairs obtained through Steane construction. There are 66 good binary codes that include 12 optimal linear codes, 45 known optimal linear codes, and nine known optimal self-orthogonal codes. The six pure binary quantum codes all achieve the performance of their additive counterparts constructed by quaternary construction and thus are known optimal codes.