一种原大成像照相架

原大成像照相架作为各刑侦工作相机的配套辅助用具,使用照相架辅助拍摄,可以得到一个与目标物同样大小且失真度最小的原大成像,使得原本需要经复杂调试也很难拍好的拍摄过程,变得非常简单、便捷,不仅可提高刑侦工作效率,而且有利于准确固定证据,尽早侦破刑事案件。

CEFR视角下英语专业学生英语能力培养探究

基于《欧洲语言共同参考框架》能力标准,具体分析我国现行英语专业教学大纲和专业八级考试大纲的能力要求,论述我国英语专业语言能力要求存在的片面性、不对应性和不系统性等问题,旨在提出整合现行英语等级考试的紧迫性和制定英语专业能力考试标准的必要性,为正在制定的英语专业能力标准提出建议。

高大英俊门将——江津

江津在你面前一站,你怎么看也看不出他是个纯种的上海人。不要说他那壮实挺拔伟岸的身躯,就是他那一口纯正的北方口音和憨厚质朴的模样,活脱脱的就是一个北方汉子。可就是这个地道的上海小伙子,却让沪上的球迷朋友心里很不是滋味。

Study of Sustained Release Phenylpropanolamine Hydrochloride Hydrophilic Matrix Tablets Containing Hydroxypropylmethylcellulose K100M and Carbopol 971P

选用HPMC K100M和卡波普971P为骨架材料，粉末直接压片法制备骨架片，考察释放度，反相高效液相色谱法检测盐酸苯丙醇胺（PPA·HCl）的浓度。释药曲线均符合Higuchi方程（R＞0．98，P＜0．01）。运用正交设计法，以美国市场的PPA·HCl缓释片Acutrim^R为对照，相似因子f2值为指标，筛选获得了最优处方。其工艺重现性合格。研制片在0．1mol·L^-1 HCl,H2O(pH6.5)，磷酸盐缓冲液（PBS）pH5.0,6.8和7.4的介质中，以及在0.1mol·L^-1HCl中释放2h，转移至PBS6．8中释放10h，相对于对照品的f2值为63－74，表明在各介质中两制剂的释药曲线相似。释药影响因素的考察结果表明：在本实验考察的范围内，骨架片在水中的释药速率与HPMC K100M和卡波普971P的用量呈负相关。HPMC K100M和卡波普971P的比例（保持聚合物总用量相同），硬脂酸镁量和骨架片硬度对释药速率无显著性影响。

Fabrication of amino-functionalized Fe_3O_4@Cu_3(BTC)_2 for heterogeneous Knoevenagel condensation

Metal organic frameworks（MOFs） are an important platform for heterogeneous catalysts.Although MOFs with a smaller particle size exhibit better catalytic performance because of less diffusion limitations,their separation and recycling after catalytic reactions are difficult.The integration of MOFs with magnetic nanoparticles could facilitate their recovery and separation.Especially,the shell thickness of the core-shell structured composites is controllable.In this study,amino-functionalized Fe3O4@Cu3（BTC）2 was fabricated by a stepwise assembly method and its catalytic performance in Knoevenagel condensation was investigated.The results demonstrated that the magnetic hybrid material exhibited a core-shell structure,with a shell thickness of about 2 00 nm.Furthermore,it not only exhibited high catalytic activity,but remarkably,it could also be easily recovered magnetically and recycled without obvious loss of catalytic efficiency after three cycles.

Metal–organic-framework-based catalysts for hydrogenation reactions

Metal-organic-framework （MOF）-based materials with novel physicochemical properties have emerged as promising catalysts for various hydrogenation reactions. In addition to metal clusters and multifunctional organic ligands, MOF-based catalysts can incorporate other functional species, and thus provide various active sites for hydrogenation processes. The structural properties of the catalysts play significant roles in enhancing the interactions among the reactants, products, and catalytic sites, which can be rationally designed. Because of the synergistic effects between the ac-tive sites and the structural properties, MOF-based catalysts can achieve higher activities and selec- tivities in hydrogenation reactions than can be obtained using traditional heterogeneous catalysts. This review provides an overview of recent developments in MOF-based catalysts in the hydro-genation of alkenes, alkynes, nitroarenes, cinnamaldehyde, furfural, benzene, and other compounds. Strategies for improving the catalytic performances of MOF-based catalysts are discussed as well as the different active sites and structural properties of the catalysts.

Ni-based catalysts derived from a metal-organic framework for selective oxidation of alkanes

Ni nanoparticles embedded in nitrogen-doped carbon（Ni@C-N） materials were prepared by ther-molysis of a Ni-containing metal-organic framework （Ni-MOF） under inert atmosphere. The as-synthesized Ni@C-N materials were characterized by powder X-ray diffraction, N_2 adsorp-tion-desorption analysis, scanning electron microscopy, transmission electron microscopy, atomic absorption spectroscopy, and X-ray photoelectron spectroscopy. The MOF-derived Ni-based mate-rials were then examined as heterogeneous catalysts for the oxidation of alkanes under mild reac-tion conditions. The Ni@C-N composites displayed high activity and selectivity toward the oxidation of a variety of saturated C–H bonds, affording the corresponding oxidation products in good-to-excellent yields. Furthermore, the catalysts could be recycled and reused for at least four times without any significant loss in activity and selectivity under the investigated conditions.

Synthesis and in-vitro characterization of biodegradable porous magnesium-based scaffolds containing silver for bone tissue engineering

Infection is a major potential complication in the clinical treatment of bone injuries. Magnesium (Mg)-based composites are biodegradable and antibacterial biomaterials that have been employed to reduce infection following surgical implants. The aim of present study was to synthesize and in-vitro characterize Mg-based scaffolds containing silver for bone tissue engineering. Porous Mg-based scaffolds with four silver concentrations (i.e., 0, 0.5 wt.%, 1 wt.%, and 2 wt.%), denoted by Mg?Ca?Mn-Zn-xAg (MCMZ?xAg)(where x is the silver concentration), were fabricated by the space holder technique. The effects of silver concentration on pore architecture, mechanical properties, bioactivity, and zone of bacterial inhibition were investigated in-vitro. X-ray diffractometry (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and fluorescence microscopy were utilized to characterize the obtained scaffolds. In-vitro corrosion test results indicated that the MCMZ scaffolds with lower silver content were more resistant to corrosion than those enriched with higher amounts of silver. Examination of the antibacterial activity showed that the MCMZ?Ag scaffolds exhibited superb potential with respect to suppressing the growth of Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), in the inhibition zone around the MCMZ?Ag scaffolds, with increasing in the amount of incorporated silver;however, higher amounts of silver increased the cytotoxicity. Taken together, the results of this study demonstrate that the porous 0.5 wt.% Ag-containing scaffolds with interconnected pores, adequate mechanical properties, antibacterial activity, and cell adhesion are promising with respect to the repair and substitution of damaged and diseased bones.

Performance-based passive control analysis of adjacent structures:Optimization of Maxwell dampers

The performance-based passive control analysis of the Maxwell dampers between one 10-story and one 6-story adjacent RC frames is conducted in this work.Not only the optimal parameters but also the optimal arrangements of the Maxwell dampers are proposed based on the optimal target of making the total exceeding probability of the adjacent structures to be minimal.The applicability of the analytical expressions of the Maxwell damper damping parameters under different seismic performance targets are firstly examined and then the preferable damping parameters of the Maxwell dampers are proposed through the extensive parametric studies.Furthermore,the optimal arranging positions and optimal arranging numbers of the Maxwell dampers between the adjacent buildings are derived based on a large number of seismic fragility analyses,as well.The general arranging laws of the Maxwell dampers between the adjacent buildings are generated based on the discussion of the theoretical method through the simplified plane model.The optimal parameters and optimal arrangement of the Maxwell dampers presented make both the adjacent structures have preferable controlled effects under each seismic performance target which can satisfy the requirements of multi-performance seismic resistance of the modern seismic codes.

2D metal‐free heterostructure of covalent triazine framework/g‐C_(3)N_(4) for enhanced photocatalytic CO_(2) reduction with high selectivity

Solar‐driven CO_(2)conversion to precious fossil fuels has been proved to become a potential way to decrease CO_(2)with producing renewable fuels,which mainly relies on photocatalysts with efficient charge separation.In this work,a metal free heterostructure of covalent triazine framework(CTF)and graphite carbon nitride(g‐C_(3)N_(4),abbreviated as CN)is applied in the CO_(2)photoreduction for the first time.Detailed characterization methods such as photoluminescence(PL)and time‐resolved PL(TR‐PL)decay are utilized to reveal the photo‐induced carries separating process on g‐C_(3)N_(4)/CTF(CN/CTF)heterostructure.The introduced CTF demonstrated a great boosting photocatalytic activity for CN,bringing about the transform rates of CO_(2)to CO reaching 151.1μmol/(g·h)with a 30 h stabilization time,while negligible CH_(4)was detected.The optimal CN/CTF heterostructure could more efficiently separate charges with a lower probability of recombination under visible light irradiation,which made the photoreduction efficiency of CO_(2)to CO be 25.5 and 2.5 times higher than that of CTF and CN,respectively.This investigation is expected to offer a new thought for fabricating high‐efficiency photocatalyst without metal in solar‐energy‐driven CO_(2)reduction.

Systems Analysis in the Study of the Political Elite

The main topic of the research is applying of systems approach in studying of political elite. This approach was applied in the analysis of Russia＇s regional power elite （1991 to 2010）. The elite was studied as a complex self-reference system oriented at its own environment, not only in an adaptive way, but first and foremost in structure. The systems approach specifies the following conceptual framework of the study： self-reference, system boundaries, and interaction between the political elite and the surrounding world. Application of the systems analysis to studying the political elite enabled to analyze the structure and functions of the elite, create a model of elitogenesis, and receive study matrix.

Developing Theoretical Relativistic Framework for Research in Open and Flexible Learning： A New Trend in Educational Research

The purpose of research study was to develop a theoretical relativistic framework for research in open and flexible learning environment because it is a new dimension in the field of education. Developing a theoretical relativistic framework for any research study is first and prime step in walking on the track to reach the distinction set by the researcher. Open and flexible learning is a new trend in education, enriched with ICT-use as a basic demand of the 21st century generation in all parts of the globe. So, it requires a theoretical framework for its initiation, implementation, development and evaluation which is relatively developed and advanced from the existing framework. In any research study the literature review is carried out in order to develop, build or construct a theoretical framework. The researcher of the study has observed while attending the international conference on ODL （AAOU, 2013） that most of the studies require theoretical underpinning for ICT-use in education. The researcher assume that being a new trend in education to use ICT for teaching learning purpose; it requires conceptual clarity and theoretical background of the user and researcher, because, without theory the practice is wastage of money, time and energy and it becomes ineffective and requires relatively new conceptual development. So, the problem stated by the researcher for the study was： Developing theoretical relativistic framework for research in open and flexible learning： A new trend in educational research. The objective of the study was integrating the interrelated concepts to build a pnemonological network for identifying the constructs in ICT-rich open and flexible learning environment. The study was significant because it provided theoretical background for conducting research in ICT-use for teaching and learning through open and flexible systems; whether blended or online learning and training. The methodology used by the researcher was qualitative and interpretive because there were reviewing of literature and meta-analysis for building the framework. The data were analyzed and interpreted by the researcher for the findings and drawing conclusions. On the basis of conclusions the researcher has made suggestions and recommendations for conducting research in open and flexible learning environment by using this theoretical relativistic framework. The framework was named as Virtual Learning Environment Framework （VLEF）.

Detection of Tetracycline Antibiotics in Water by Dispersive Micro-solid Phase Extraction using Fe_(3)O_(4)@[Cu_(3)(btc)_(2)]Magnetic Composite Combined with Liquid Chromatography-Tandem Mass Spectrometry

Residues of tetracycline antibiotics(TCs) in environments may be harmful to human.Due to their high polarities,it is extremely challenging to efficiently enrich TCs with low concentrations in natural waters for analysis.In this work,a magnetic metal-organic framework Fe_(3)O_(4)@[Cu_(3)(btc)_(2)]was synthesized and applied as a dispersive micro-solid phase extraction adsorbent for TCs enrichment.Effects of dispersive micro-solid phase extraction conditions including extraction time,solution p H,and elution solvent on the extraction efficiencies of TCs were investigated.Results show that TCs could be enriched efficiently by Fe_(3)O_(4)@[Cu_(3)(btc)_(2)],and electrostatic interaction between TCs and Fe_(3)O_(4)@[Cu_(3)(btc)_(2)]dominated this process.Combined with liquid chromatography-tandem mass spectrometry,four TCs residues (oxytetracycline,tetracycline,chlortetracycline,and doxycycline) in natural waters were determined.The detection limits (LOD,S/N=3) of the four antibiotics were 0.01-0.02μg/L,and the limits of quantitation (LOQ,S/N=10)were 0.04-0.07μg/L.The recoveries obtained from river water and aquaculture water spiked with three TCs concentration levels ranged from 70.3%to 96.5%with relative standard deviations of 3.8%-12.8%.Results indicate that the magnetic metal-organic framework based dispersive micro-solid phase extraction is simple,rapid and high-loading for antibiotics enrichment from water,which further expand the practical application of metal-organic frameworks in sample pretreatment for environmental pollutant analysis.

A Simplified Method for Analyzing Truss Structure Due to Removal of Members

Based on relating equation group, a simplified method was presented in terms of the matrix displacement method, which can be conveniently used to study the re-distribution of the internal forces and displacement of truss structures due to the removal of members. Such removal is treated as though adding a load case to the original truss, and the re-distribution can be calculated without modifying the original global stiffness matrix. The computational efficiency of the presented method is faster by square times than that of the matrix displacement method. The results from the two methods are identical.

Introducing Stakeholder-Based Frameworks for Post-merger Integration （PMI） Success

The importance of stakeholder relationship management for successful integration in post-merger management is not doubted. The establishment of a new powerful trend in investments produces strategic shifts in strategic management. Shareholder wealth maximization way of thinking is changing to stakeholder wealth maximization where a company＇s value management system is based not only on economic profit maximization, but also on environmental, social, and governance （ESG） maximization. There is especially a high need for a management system that can be used by mergers and acquisitions （M＆A） practitioners during integration process. There is a critical need for metrics which can trace the interests of all stakeholders, because to achieve success in integration, it is no longer acceptable for management to focus solely on the needs of one or two stakeholder groups. In this article, the authors have introduced two frameworks： sun cube and stakeholder relationship matrix. These tools can be useful in mergers and acquisitions （M＆A） process for conducting a stakeholder analysis.

N-doped carbon-coated Fe_(3)N composite as heterogeneous electro-Fenton catalyst for efficient degradation of organics

Herein,the application of a N-doped graphitic-carbon-coated iron nitride composite dispersed in a N-doped carbon framework(Fe_(3)N@NG/NC)is investigated as a heterogeneous electro-Fenton(HE-EF)catalyst for the efficient removal of organics.The simultaneous carbonization and ammonia etching of iron-based metal organic framework(Fe-MOF)materials yielded well-dispersed N-doped carbon-coated Fe_(3)N nanoparticles with a diameter of~70 nm.The Fe_(3)N and pyridinic N endowed the composite with high HE-EF activity for decomposing the electrogenerated H_(2)O_(2) to•OH.The Fe_(3)N@NG/NC exhibited outstanding HE-EF performance in removing various organic pollutants with low iron leaching.A removal rate of 97-100%could be obtained for rhodamine B(RhB),dimethyl phthalate,methylene blue,and orange Ⅱ in 120 min at a pH of 5.0.When the solution pH was set to 3.0,5.0,7.0,and 9.0,the removal rate of RhB reached 100%,96%,92%,and 81%,respectively,in 60 min at an optimum voltage of 0.0 V(vs.reversible hydrogen electrode(RHE)).Moreover,the concentration of leached iron was expected to be below 0.03 mg/L in a wide pH range of 3.0-9.0.In addition,the RhB removal efficiency remained as high as 90%after six cycles in the reusability experiments.This work highlights the MOF-derived Fe_(3)N composite as an efficient HE-EF catalyst and the corresponding catalytic mechanism,which facilitates its application in wastewater treatment.