Rational Synthesis of Crystalline Covalent Triazine Framework with Methylthio Pendant Arms for Efficient Mercury(Ⅱ)Adsorption

The interest in curtailing environmental pollution issues through physical separation processes has inspired an extensive search for novel nanoporous materials with exceptional adsorption capabilities.Covalent triazine frameworks(CTFs),emerged as a class of crystalline covalent organic frameworks(COFs),have been widely examined for various separation applications,owing to their large porosity,high stability,and rich nitrogen(N)doping.The development of CTFs for efficient adsorption of mercury(Ⅱ)(Hg^(2+))is of great importance for the field,whereas it is rarely attempted,on account of limited synthetic strategies and unknown structural-property relations of conventional CTFs derived from ionothermal approaches.Herein,we report rational synthesis of a crystalline CTF with methylthio pendant arms for efficient removal of Hg^(2+)with an exceptional capacity of 751 mg·g^(-1),ranking at the top among previously-reported adsorbents.This work may open up new possibility in the synthesis of COFs for various separations.

Generation and Suppression of Pendant Droplet Oscillation in Electron Beam Directed Energy Deposition

Electron beam–directed energy deposition(EB–DED)has emerged as a promising wire-based metal additive manufacturing technique.However,the effects of EBs on pendant droplets at wire tips have not yet been determined.The aim of this study is to enhance the understanding of this action by analyzing the mechanism of droplet oscillation.The pendant droplet oscillation phenomenon hinders the stable transfer of droplets to the molten pool and limits the feasibility of manufacturing complex lattice structures by EB–DED.Hence,another aim of this study is to create an oscillation suppression method.An escalating asymmetric amplitude is the main characteristic of droplet oscillation.The primary oscillationinducing force is the recoil force generated from the EB-acted local surface of the droplet.The physical mechanism of this force is the rapid increase and uneven distribution of the local surface temperature caused by the partial action of the EB.The prerequisites for droplet oscillation include vacuum conditions,high power densities,and bypass wire feeding processes.The proposed EB–dynamic surrounding melting(DSM)method can be applied to conveniently and effectively suppress oscillations,enable the accurate transfer of droplets to the molten pool,and achieve stable processes for preparing the strut elements of lattice structures.Lowering the temperature and improving the uniformity of its distribution are the mechanisms of oscillation suppression in EB–DSM.In this study,the physical basis for interpreting the mechanism by which EBs act on droplets and the technical basis for using EB–DED to prepare complex lattice structure parts are provided.

Evolution of a Water Pendant Droplet: Effect of Temperature and Relative Humidity

As part of a better understanding of drying liquids within porous materials, measurements from 293 to 343 K of deionized water surface tension in air as a function of relative humidity are exposed. Experimental work was carried out using the pendant drop method coupled with image analysis within an adapted instrumented climatic chamber. Results show that surface tension linearly decreases when relative humidity increases. Although the effect of humidity is less compared to that of the temperature and even less compared to a surfactant impact, it must not be neglected and values have to be mentioned when dealing with water evaporation. Modifying surface tension also affects the pendant drop shape. The drying kinetics of the pendant drop volume and its outer shell are connected to this change of shape. Steam in the air can be assimilated to a wetting agent, hence a surfactant, and can be used in an environmental-friendly way to ease the drying stage. Indeed, the challenge is to limit the risk of cracking and damaging pieces during this crucial step in material processing.

Synthesis and Structure of a New Bicadmium (Ⅱ) Complex with Macrocyclic Hexaaza Bearing Hydroxyethyl Pendants

A new bicadmium(??) complex [Cd2L](ClO4)2?1.25H2O (C28H35Cd2Cl4N6O13.25) was synthesized and characterized by X-ray diffraction and ES mass spectral analyses. It crystallizes in the triclinic system, space group P1 with a = 15.630(3), b = 15.990(3), c = 16.330(3) ?, α = 89.90(3), β = 68.87(3), γ = 87.94(3)o, V = 3804.1(13) ?3, Mr = 1034.22, Z = 4, F(000) = 2060, Dc = 1.806 g/cm3, T = 293(2) K, μ = 1.468 mm-1 and λ = 0.71073 ?. The structure was refined to R = 0.0779 and wR = 0.1960 for 7034 observed reflections with I > 2σ(I).

Optimization of Serial Port of General Flex Pendant for Industrial Robot

In order to further improve the serial ports communication mode of the general Flex Pendant for industrial robot,a multiple serial communication mode is put forward. It is used to meet the stability of data transmission,transmission distance,transmission speed,anti-interference and cost-effective. Using ADUM1201 single direction dual channel digital isolator,two pieces of MAX13487 E and a piece of MAX3232 chip to transmit data and files, and to control chip’ s electrical level. Selecting the RS232, RS422 and RS485 communication mode,the serial ports of the general Flex Pendant of industrial robot is optimized.

EXCIPLEX FORMATION OF A POLYESTER WITH A TEREPHTHALATE MAIN CHAIN HAVING A PENDANT N, N-DIMETHYLAMINO GROUP

The fluorescence behaviours of a new polymer poly [oxy-2 (4-N, N-dimethylaminobenzyl) propane-1 , 3-diyloxy-terephthaloyl] (Ⅰ) in solution were studied. Inter-and intra -molecular exciplex is formed between the singlet excited state of N, N- dimethylanilino group (abbreviated to DMA) and the ground state of terephthalate group (abbreviated to TP). The intensity ratio of the long wavelength exciplex fluorescence to the short wavelength emission of DMA group is used as an index for the inter-and intra-molecular interaction of chromophores. The results are compared with model polymer polyoxy-2-(4-N ,N-dimethylaminobenzyl) propanc-1 , 3-diyloxyadipoyl (Ⅱ), model monomer compound 4-N, N-dimethylaminobenzylmethyl terephthalate(Ⅲ) and diethyl 2-( 4-N, N-dimethylaminobenzyl) malonate (Ⅳ). Polymer association derived by electron donor and acceptor interaction (EDA) is further verified as a key role in the interpolymer exciplex formation . The fluorescence decay time of (Ⅰ) and monomer (Ⅲ) are measured in solutions.

SYNTHESIS， COMPLEXATION PROPERTIES AND CRYSTAL STRUCTURE OF NEW DIOXOCYCLAM BEARING 8－METHYL QUINOLINE AS FUNCTIONAL PENDANT（S）

Two new dioxo tetraamine ligands L1 and L2 have been synthesized and characterized by 1H NMR, IR, MS and elemental analysis,Their protonation eonstants and complex formation constants with Cu2+have been determined by potentiometric titration, The X-ray crystal structure of L1 has been determined.

Huabao Electrical Appliances Factory——World's Biggest Pendant Lamp Factory

Started with 100 workers and staff, the Guangdong based Huabao Electrical Appliances Factory has now made 500 products in 50 categories. It boasts 2,000 staff and fixed assets worth RMB80 million. In 1988, the factory was cited as an advanced enterprise in earning foreign exchange among light industries nationwide, by the Ministry of Light Industry; and Huabao electrical appliances were named high quality products in an appraisal sponsored by the Ministry of Light Industry.

Health benefits of pendant from the viewpoint of Persian medicine

Background:Reviewing historical evidence in the various schools of traditional medicine shows that numerous methods have been used to maintain human good health and treatment of diseases.Persian medicine(PM)scholars have been employed different methods to prescribe medications,which can be classified into two main groups:internal uses,including oral,parenteral,and anal,and also external uses such as topical,transdermal,and applying pendants.In this study,we aim to introduce some of the therapeutic pendants.Methods:We reviewed the most famous PM textbooks and current evidence in relevant databases such as PubMed,Science Direct,Scopus,Google scholar and SID related to the topic.Results:In this study,about 100 traditional therapeutic substances were found and finally,thirty-two of them were represented.They were often stones,and some of them were other materials such as metals,gums,and herbs.According to the PM,the utilization of pendants,in addition to cosmetic purposes,has been considered to maintain the health and treatment of some diseases.Therapeutic pendants can be considered as a kind of external medication use in which therapeutic materials are hung on the body surface.The external use of pendants could have curative effects with their close contact to the body surface.Conclusion:Pendant therapy may probably be considered as a non-invasive and easy-to-use treatment with unnoticeable side effects that can be utilized along with other therapies.

Syntheses,Spectral Characterization of the Nickel(Ⅱ) Complexes of Macrocyclic Dioxotetraamine and the Effect of the Functional Pendant Arms on their Properties

A series of new macrocyclic dioxo 13 aneN 4 bearing various functional pendants, 2 methylfuran (LF), 2 methylthiophene (LT), 2 methylpyridine (LP), have been synthesized and characterized, where dioxo 13 aneN 4 is 1,4,7,10 tetraazacyclotridecane 11,13 dione. The solution behaviours of the nickel(Ⅱ) complexes have been studied by Uv vis, cyclic voltammetric techniques. The red shifts were observed for the absorption band maxima of the electronic spectra from NiLR 1 to NiLR 2 (R=2 methylfuran, 2 methylthiophene, 2 methylpyridine). The value of E 1/2 of the NiLR 2 is less than NiLR 1 and both of them are lower than that of the nickel(Ⅱ) complex of the unsubstituted ligand, and these reasons are discussed.

Preparation and Characterization of Maltose-Pendant Polymer/Mica Nanocomposites and Their Application to Oxygen Gas Barrier Films

Maltose-pendant polymer/mica nanocomposites were prepared by a solution intercalation method. For organic composite part, 1) maltose-pendant polymer (homopolymer) and 2) the copolymer of maltose-pendant monomer and a small amount of N,N-Dimethylamino propylacrylamide, methyl chloride quartenary were used. The morphological studies (XRD and FE-SEM) revealed that the hybrid of maltose-pendant polymer was a conventional phase separated composite. On the other hand, the hybrid using the copolymer exhibited exfoliated structure. Both the conventional composite of maltose-pendant polymer and the nanocomposite of copolymer were applied to a coating material for oxygen gas barrier layer on a nylon-6 film, and oxygen transmission rates of the films were evaluated. Maltose-pendant polymer had a good oxygen barrier property under dry condition, and the barrier property under wet condition was improved by the hybridization with mica. In contrast, the barrier property of copolymer was slightly inferior to that of maltosependant polymer. However, under dry condition, it can be seen that the nanocomposite of copolymer improves the barrier property more effectively than the case of conventional composite of maltose-pendant polymer.

双酚S型含侧苯基杂环共聚醚砜的合成和性能

为了开发耐高温、可溶解、易于功能化改性的聚芳醚砜,以4-(3-苯基-4-羟基苯基)-2,3-二氮杂萘-1-酮、4,4′-二羟基二苯砜和4,4′-二氯二苯砜为单体,采用高温溶液缩聚法合成一系列不同单体比例的含侧苯基杂环共聚醚砜(PPESS-Ps)。利用核磁共振氢谱、红外光谱和X射线衍射表征了PPESS-Ps结构,并测试了PPESS-Ps的特性黏度、分子量、热性能、溶解性、力学性能以及亲水性。结果表明,PPESS-Ps化学结构符合预期,共聚组成可控,其特性黏度介于0.79~0.92 dL/g,数均分子量在2.75×10~4~4.65×10~4之间;PPESS-Ps属于无定形聚合物,其玻璃化转变温度大于245℃,5%热失重温度高于511℃,800℃下残炭率超过40.6%,耐热性好且热稳定性优异;PPESS-Ps能溶于N-甲基吡咯烷酮、N,N-二甲基乙酰胺以及氯仿等有机溶剂中,并且表现出优良的力学性能,其拉伸模量在1.61~1.92 GPa之间,拉伸强度介于55~81 MPa。

含苯磺酸侧基杂萘联苯聚醚砜纳滤膜的制备与性能

将含苯磺酸侧基杂萘联苯聚醚砜(SPPES-P-H)浸泡于氯化钠溶液中得到含苯磺酸钠侧基杂萘联苯聚醚砜(SPPES-P-Na),采用涂覆法制备含苯磺酸侧基杂萘联苯聚醚砜复合纳滤膜,考察聚合物浓度、热处理条件对复合纳滤膜性能的影响.结果表明,SPPES-P-Na复合纳滤膜的通量高于SPPES-P-H复合纳滤膜的通量;当SPPES-P-Na的质量分数为1.5%,热处理温度为100℃,热处理时间为30 min时,复合膜的水通量达到58.0 L/(m^(2)·h),Na_(2)SO_(4)的脱盐率为89.0%;当操作温度为95℃时,复合膜的水通量为205.0 L/(m^(2)·h),对Na_(2)SO_(4)的脱盐率为82.0%,表现出良好的耐热性;将复合膜在质量浓度0.2 g/L的次氯酸钠溶液中浸泡10 d,性能无明显变化,表现出优异的耐氯性.

阻尼硅橡胶共混物及复合材料的研究进展

简要介绍了硅橡胶的结构特征及常见的阻尼改性方法。重点介绍了共混改性、添加填料或阻尼剂等改性方法对硅橡胶阻尼性能的影响及国内外研究现状,还介绍了通过引入悬挂链提高阻尼性能的新型阻尼改性方法。

基于重叠网格的皮蛋喷淋涂膜仿真研究

为了加深对皮蛋喷淋涂膜工艺的认识,使用Fluent软件中重叠网格耦合VOF模型开展两相流研究,获得皮蛋不同摆放姿势下的液膜润湿比,并以膜厚变化指数为响应值,结合Box-Behnken试验筛选出悬垂液滴去除时最优吸管参数与工作压力,结果显示:尖端朝下摆放的皮蛋经过喷淋后液膜润湿比为1,而钝端朝下摆放的皮蛋经过喷淋后液膜润湿比仅为0.836,筛选出最优吸管参数组合为间距14.50 mm、直径12.09 mm、工作压力6.97 kPa、膜厚变化指数预测值为0.636。在最优吸管参数组合下进行仿真试验,并利用气吸装置开展悬垂液滴去除试验,试验结果显示,膜厚变化指数仿真值与预测值的相对误差为1.73%,膜厚变化指数的实际值与预测值的相对误差为7.55%,与仿真值的相对误差为9.12%。结果表明本研究的耦合模型可用于皮蛋喷淋涂膜仿真试验。

Reciprocal Distance Laplacian Eigenvalue Distribution Based on Graph Parameters

Let G be a connected graph of order n and m_(RD)^(L)_(G)I denote the number of reciprocal distance Laplacian eigenvaluesof G in an interval I.For a given interval I,we mainly present several bounds on m_(RD)^(L)_(G)I in terms of various structuralparameters of the graph G,including vertex-connectivity,independence number and pendant vertices.

基于有限元分析的医用桥梁式吊塔轻量化设计研究

目的:为解决医用吊塔由于质量与体积过大所带来的安全风险和安装维护困难的问题,基于有限元分析对医用桥梁式吊塔进行轻量化设计。方法:采用Altair HyperWorks CAE平台建立医用桥梁式吊塔悬梁的有限元模型,在刚度和强度计算结果的基础上对其进行拓扑优化及尺寸优化。比较优化前后医用桥梁式吊塔悬梁端部的变形角度、最大应力及质量,并完成优化方案验证。结果:优化后的医用桥梁式吊塔悬梁模型相比原模型变形角度仅增加了0.05°,最大应力仅上升了9.1%,但质量减轻了20.2%。在4倍承载条件下优化后的医用桥梁式吊塔悬梁最大应力为240 MPa,承载性能满足相关要求。结论:该研究在保证医用桥梁式吊塔悬梁的刚度和强度性能满足要求的同时,实现了悬梁的轻量化设计。

吊钟花观赏价值与培育要点

吊钟花属植物作为杜鹃花科植物重要的代表之一,是一种具有很高观赏价值的重要植物资源。本文简要阐述了其观赏价值,然后重点从扦插、土壤要求、光照条件、温度条件以及浇水方法等方面论述了吊钟花的培育要点,并且对吊钟花常见的病虫害以及防治措施进行了探讨,以期为吊钟花培育提供相关技术参考。

光纤泡沫铝板施工技术研究与应用

光纤泡沫铝板属于新型材料,凭借自重轻、强度高、隔声效果好、耐火耐高温、易加工切割开孔等优势,受到广泛关注。目前光纤泡沫铝板施工尚无操作规程和技术标准,常规的安装方式难以满足需求。本技术通过采用镶嵌安装工艺,有效解决光纤泡沫铝板安装的难题,保证了光纤泡沫铝板安装的稳定可靠性。

给定悬挂点数的树和单圈图的顶点度函数研究

设G是n阶简单图,G的悬挂点数记作p(G),顶点度函数指数H_(f)(G)定义为H_(f)(G)=∑_(v∈V(G))f(d(v)).考虑在给定悬挂点数为k的n阶树和单圈图中,在f(x)是严格凸函数的情况下,顶点度函数H_(f)(G)的最大值问题.在f(x)是严格凹函数的情况下,同样的结果也适用于顶点度函数H_(f)(G)的最小值问题.通过对这些情况的分析,得出了顶点度函数H_(f)(G)在给定条件下的最值性质.这些结果对理解图论中的悬挂点和顶点度函数的性质具有重要意义.