摘要：Carbon nitride has drawn numerous eyes in the past decade,whereas the photocatalytic performance is significantly limited by its wide band-gap(~2.7 e V for C_(3)N_(4))***,C_(3)N_(5)with narrower band-gap has been reported,however,a systematically investigation on its photoactivity for H_(2)production has not been *** present work demonstrates the synthesis of C_(3)N_(5)by thermal treatment of 3-amino-1,2,4-triazole,and the photocatalytic performance for H_(2)production of C_(3)N_(5)is investigated *** H_(2)production rate of C_(3)N_(5)is~2.2 times higher than that of C_(3)N_(4) with 1.0 wt%Pt as co-catalyst,and series of experiments are carried out to explore the behind elements accounting for the high *** the results of DRS,PL and photocurrent,it is found that C_(3)N_(5)possesses wider visible light absorption region,lower band-gap and quicker photogenerated e^(-)/h^(+)separation ***,characterizations including in-situ DRIFTS are adopted to monitor the adsorption property of H_(2)O on C_(3)N_(5),which plays a significant role in surface water reduction reaction,and higher amount of adsorbed H_(2)O molecules on C_(3)N_(5)is *** present work exhibits new insights into the high photocatalytic performance of N-rich carbon nitride catalysts.

摘要：Photocatalytic oxidative organic reactions are important synthetic transformations,and research on reaction selectivity by reactive oxygen species(ROS)is *** date,however,there has rarely been any focus on the directed generation of ***,we report the first identification of tunable molecular oxygen activation induced by polymeric conjugation in nonmetallic conjugated microporous polymers(CMP).The conjugation between these can be achieved by the introduction of alkynyl ***-A with an alkynyl bridge facilitates the intramolecular charge mobility while CMP-D,lacking an alkynyl group enhances the photoexcited carrier build-up on the surface from *** different processes dominate the directed ROS generation of the superoxide radical(·O_(2)^(-))and singlet oxygen(^(1)O_(2)),*** theory is substantiated by the different performances of these CMPs in the aerobic oxidation of sulfides and the dehydrogenative coupling of amines,and could provide insight into the rational design of CMPs for various heterogeneous organic photosynthesis.

摘要：In this work,the tunable introduction of oxygen vacancies in bismuth tungstate was realized via asimple solvothermal method with the assistance of iodine *** the predictions afforded bytheoretical calculations,the as-prepared bismuth tungstate was characterized using various tech-niques,such as X-ray diffraction,Raman spectroscopy,scanning electron microscopy,transmissionelectron microscopy,X-ray photoelectron spectroscopy,electron spin resonance spectroscopy,anduV-Vis diffuse reflectance *** different concentrations of the oxygen vacancies onbismuth tungstate were found to be intensely correlated with iodine doping,which weakened thelattice oxygen *** to the sufficient oxygen vacancies introduced in bismuth tungstate as aresult of iodine doping,the molecular oxygen activation was remarkably enhanced,thus endowingbismuth tungstate with high activity for the photocatalytic degradation of sodium *** encouraging is the total organic carbon removal rate of sodium pentachlorophenateover iodine-doped bismuth tungstate that exceeded 90%in only 2 h and was 10.6 times higher thanthat of the pristine bismuth tungstate under visible light ***,the mechanism,through which the degradation of sodium pentachlorophenate over iodine-doped bismuth tung-state is enhanced,was speculated based on the results of radical detection and capture *** work provides a new perspective for the enhanced photocatalytic degradation of organochlo-rine pesticides from the oxygen vacancy-induced molecular oxygen activation over iodine-dopedbismuth tungstate.

摘要：Porous organic polymers(POPs)are an emerging class of porous materials,having many promising applications in a variety of *** them,covalent triazine frameworks(CTFs)featuring conjugated and porous structures can be well applied in *** achieve high optoelectronic performance,usually the design and synthesis of CTFs based on appropriate building blocks is *** we report the synthesis of two fluorescent CTFs based on typical fluorescent building blocks,in which CTF-Py constructed from a pyrene(Py)building block was reported for the first time,showing prospective applications in the sensing of nitroaromatics with high sensitivity,and photocatalytic water splitting and carbon dioxide reduction with high performance in comparison with other porous organic materials.

摘要：Engineering an efficient interface is a trustworthy strategy for designing advanced photocatalytic systems for solar energy ***,oxygen-deficient Bi_(2)WO_(6)atomic layers without organic residues were successfully fabricated via a facile solvothermal strategy by the multifunctional regulatory mechanism of introduced *** DFT calculations and speciation determination revealed that chloridion displayed a more pronounced effect in the controllable synthesis of oxygen-deficient Bi_(2)WO_(6)atomic layers without organic residues:ultrathinning and *** built-in multi-cooperative interface endowed Bi_(2)WO_(6)with intriguing photoelectrochemical properties,O_(2) activation ability,and ultrahigh activity in visible-light powered deep oxidation of NO.A reasonable photocatalytic mechanism was proposed based on in situ infrared spectroscopy analysis and theoretical *** believe that this multi-cooperative interface engineering of oxygen-deficient Bi_(2)WO_(6)atomic layers without organic residues could provide new insights into the design of two-dimensional(2D)layered materials with efficient active sites and pave the way for efficient NO photooxidation systems.

摘要：氢能是重要的清洁能源,如何低成本获取氢能是其走向实际应用的重要挑战.利用太阳能驱动半导体光催化剂分解水制氢是解决这一挑战的理想途径之一.光催化全解水包括两个半反应,即析氢反应(HER)和析氧反应(OER).其中,光催化OER半反应涉及四个电子的转移(包括O–H键断裂和O–O键形成),其动力学速率远低于两电子转移的HER半反应,因此被认为是光催化全解水的决速步骤.欲实现高效光催化全解水,首先需解决光催化OER半反应动力学缓慢的问题,因此开发高效的OER光催化剂成为当务之急.受单原子催化剂的启发,本文设计并合成了联吡啶基共价三嗪框架(CTF-Bpy),因CTF-Bpy骨架上存在周期性的联吡啶官能团作为金属配位位点,并且有很好的结晶性以及合适的能带结构,是良好的光催化OER反应载体材料.然后通过简单的浸渍配位处理,将单位点的钴作为助催化剂引入到CTF-Bpy中,并用于光催化OER.X射线光电子能谱和X射线近边吸收光谱结果表明,钴是以单位点的Co^(2+)形式存在的.在可见光(λ≥420 nm)照射下,CTF-Bpy-Co在初始1 h内的平均析氧速率为3359μmolg^(–1)h^(–1),5 h内的平均析氧速率为1503μmolg^(–1)h^(–1),光催化性能超过大多数多孔有机聚合物基光催化剂.在420 nm单波长氙灯照射下,CTF-Bpy-Co的光催化析氧表观量子产率(AQY)为0.466%.此外,CTF-Bpy-Co可实现连续析氧40 h,总析氧量可达到180μmol.为明确单位点钴在光催化OER中所起的重要作用,采用相同钴含量的不同形式钴基粒子(游离的Co^(2+),Co,CoO,Co_(2)O_(3)和Co(OH)_(2))作为助催化剂引入CTF-Bpy骨架中进行对比.结果发现,配位的CTF-Bpy-Co表现出最好的光催化析氧效果,表明单位点钴在光催化OER中具有较大的优势.采用密度泛函理论研究了CTF-Bpy-Co的差分电荷密度,并结合上述实验结果提出了CTF-Bpy-Co光催化OER的机理:在可见光激发下,CTF-Bpy-Co光催化剂产生了光生电子和空穴,然后光生电子和空穴被分离并转移到光催化剂与水之间的界面.差分电荷密度证实了电子主要分布于三嗪位点周围,被Ag^(+)迅速捕获生成Ag纳米颗粒;空穴主要分布在Bpy-Co附近,单位点钴可以作为空穴的捕获中心,迅速将Co^(2+)氧化为更高价态的Co^(3+),并与界面上的水分子发生氧化反应产生氧气回到基态,完成整个光催化分解水反应循环.综上所述,为了解决光催化OER的瓶颈问题,本文提出了在催化剂中引入单位点金属助催化剂的策略,显著提升了光催化析氧性能.本研究也为实现更高效的无牺牲剂条件下的光催化全解水提供参考.

摘要：为有效减缓刀具磨损并尽可能地提高加工效率,采用Box-Behnken响应面与多元非线性回归相结合的方法,分析切削参数效应的显著性及交互作用机理,并拟合含有交互效应的刀具磨损回归方程;基于NSAG-Ⅱ算法,以切削参数为设计变量,刀具磨损回归方程和加工效率方程作为多目标优化函数,优化切削参数以实现减小刀具磨损速度的目的。结果表明,进给量与主轴转速间存在显著的正向交互效应,建立的刀具磨损回归方程在95%的置信区间内的最大拟合差值不超过0.000 6,优化结果与数值模拟结果的误差不超过2%,可有效降低刀具磨损。

摘要：利用Moldflow软件对液袋用阀门的壁厚、工艺参数、充填过程、体积收缩率和翘曲变形量进行了模流分析。以流道直径、熔体温度、注射时间和模具温度4个因素为变量,设计了一个4因素3水平的正交试验。选取阀门的体积收缩率与最大翘曲变形量作为正交试验的判断标准,对相关的模拟结果进行极差分析。结果表明,当流道直径为6~8 mm、熔体温度为180℃、注射时间为25 s、模具温度为40℃时,阀门结构和性能最为合理。

摘要：研究搭建了一小试规模的潜热储能系统,能对200~300℃的热量进行存储、释放,通过不同方式表征所使用相变材料的物理性质,研究其与应用场景的匹配性,同时分析所设计系统循环过程中的参数变化,研究系统热力特性。试验结果表明:所用二元硝酸盐能够稳定的储存温度200~290℃的余热,所使用的带螺旋型翅片换热管的潜热储能系统具有较高的热效率,试验台储热耗时51.75 min,完成47.809 MJ的能量储存,放热耗时43.5 min,释放出46.209 MJ能量,系统的储热效率为79.16%,放热效率为79.15%。在系统的循环过程中,系统累计输入能量60.398 MJ,输出能量36.578 MJ,循环效率为60.56%。

摘要：秦腔是流行于西北地区的主要戏曲剧种之一。秦腔在明代已经成形,清朝传入新疆,在乌鲁木齐形成了秦腔班社——新盛班。新盛班是秦腔传入乌鲁木齐的第一个班社,是秦腔在新疆乌鲁木齐的发展先驱,也是乌鲁木齐市秦剧团的前身。