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).

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.

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.

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.

Effects of piperacillin synthesis on the infterfacial tensions and droplet sizes

Piperacillin is a polar organic substance,and can reduce the interfacial tension of oil and water when dissolved in water.In this study,changes in dichloromethane–water interfacial tensions and microdroplet sizes during piperacillin synthesis from an aqueous solution of ampicillin and dichloromethane solution of 4-ethyl-2,3-dioxo-1-piperazine carbonyl chloride(EDPC)were observed using a pendent drop technique and a coaxial ring tube system with embedded high-speed camera,respectively.It was found that the rapid N-acylation reaction caused the piperacillin at the interface to synthesize rapidly and diffuse out slowly,resulting in the interfacial tension decreased from 19.5 m N·m-1 to 7.2 m N·m-1 rapidly and then increased slowly as the concentrations of ampicillin and EDPC were 0.05 mol·L-1 and 0.1 mol·L-1.Meanwhile,the increase in the concentration of EDPC increased the peak concentration of piperacillin at the interface,and the addition of ethyl acetate to the ampicillin solution promoted mass transfer and reduced the aggregation of piperacillin effectively.During synthesis,the interfacial tension decreased,leading to a change in droplet sizes in the micro-reaction system.The two-phase reaction was carried out in a coaxial ring tube,with ampicillin and EDPC solutions as continuous and dispersed phases,respectively.The reaction reduced the dripping flow area,and the addition of ethyl acetate to the ampicillin solution slightly affected the division of the flow pattern.Under the same flow conditions,the droplet sizes of the reaction group were smaller than those of the no reaction group.The experimental results demonstrated that the increase of the continuous phase,decrease in the dispersed phase flow rate,or increase in EDPC concentration making droplet sizes smaller,and the addition of ethyl acetate slightly affected droplet sizes.These findings are important for the design and optimization of piperacillin synthesis reactors.

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 CHARACTERIZATION OF POLY{4-[2-(tert-BUTYLDIMETHYLSILOXY)ETHYL]STYRENE}AND ITS HYDROLYSIS DERIVATIVE

The living cationic polymerization of 4-[2-(tert-butyldimethylsiloxy)ethyl]styrene (TBDMES) was studied in methylcyclohexane (MeChx)/methylchloride (MeCl) (50/50 V/V) solvent mixture at -80 degrees C. The initiator 1,1-diphenylethylene (DPE) capped 2-chloro-2,4,4-trimethylpentane (TMPCl) was formed in situ in conjunction with titanium tetrachloride (TiCl(4)). The Lewis acidity of TiCl(4) was decreased by the addition of titanium(IV) isopropoxide (Ti(OiPr)(4)) to accomplish living polymerization of TBDMES. Hydrolysis of poly(TBDMES) in the presence of tetra-butylammonium fluoride yielded poly[4-(2-hydroxyethyl)styrene] (poly(HOES)). FT-IR, NMR and DSC demonstrated the hydrolysis was complete.

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.

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.

SYNTHESIS OF NOVEL HYDROPHILIC BIODEGRADABLE POLYESTER WITH FUNCTIONALIZED SIDE CHAIN GROUPS

A substituted glycolide, 3-benzyloxymethyl-1,4-dioxane-2,5-dione, was synthesized. It is a suitable precursor for the preparation of a new hydrophilic biodegradable poly(a-hydroxy acid). The polymerizations were carried out in bulk in the presence of Sn(Oct)(2) at 120-140 degreesC. The resulting polymers were subjected to hydrogenolysis with a Pd/C catalyst in a mixed solvent to remove the protecting benzyl groups. A novel poly(a-hydroxy acid) with pendant hydroxy groups was obtained. The hydrophilicity of the resulting polymer was evaluated preliminarily.

SYNTHESIS AND CHARACTERIZATION OF PHTHALAZINONE POLY(ARYL ETHER SULFONE KETONE)WITH CARBONYL GROUP

A kind of novel heat-resistant, high performance engineering thermoplastic phthalazinone poly(aryl ether sulfone ketone) (PPESK) containing a carboxyl group in its side chain was prepared by the nucleophilic displacement reaction of 4-(4-hydroxylphenyl)- 1 (2H)-phthalazinone with di(4-chlorophenyl) sulfone, 4,4'-difluoro-benzophenone and phenolphthalin in sulfolane in the presence of K2CO3 to produce high molecular weight polymers which can be dissolved in some polar solvents such as chloroform and nitrobenzene at room temperature and can be easily cast into flexible, yellowish and transparent films. PPESK is an amorphous polymer having a decomposition temperature above 400degreesC, which indicates that it has high thermal stability. At the same time, the thermal properties of PPESKs with dicyandiamide (DICY) as curing agent indicated that the heat-resistance properties of the PPESKs are improved after curing. The apparent activation energy (A-E) of the cross-linking reaction and the reaction order (n) of PPESK/DICY were found to be 52.2 kJ/mol and ca. 1.0, respectively. Therefore, the cross-linking reaction is approximately a first order reaction.

GRAFT POLYMERIZATION OF ACRYLAMIDE ONTO HOMOPOLYMER OF 5-METHYL-5-HEXEN-2, 4-DIONE INITIATED BY CERIC ION

The homopolymerization of 5-methyl-5-hexen-2,4-dione (methacryloylacetone, MAA), a vinyl monomer having beta-diketone group, was carried out in the presence of benzophenone (BP)/N, N-dimenthyl-4-toluidine (DMT) system. Graft polymerization of acrylamide initiated by eerie ion onto the homopolymer film was investigated and the mechanism of the grafting reaction was proposed on the basis of ESR study. The grafted copolymer was characterized by means of grafting percentage, water absorption, XPS spectra and scanning electron photomicrographs.

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.

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.

Effects of dynamic deformation of pendant water drops on the electric field between hollow porcelain insulator sheds under extreme rainfall

Hollow porcelain insulators in substations are frequently confronted with rain flashovers under extreme rainfall.This study aims to investigate the spatial and temporal variation of electric fields between hollow porcelain insulator sheds affected by dynamic deformation of pendant water drops and effects of the dimensionless number of fluids,the Weber number(We)and the electric Bond number(BoE),on it for influencing factors'analysis.Flow‐electric field coupling simulations were carried out to compute the magnitude and the position of AC electric fields between the sheds.The results show that the maximum electric field at a point in time(Etmax)increases significantly after the breakup of the pendant water drop,and its position alters accordingly.For low We and BoE,the global maximum electric field(Egmax)increases with increasing We and BoE,respectively.It is much closer to the adjacent sheds and occurs later than Etmax at the breakup of the pendant water drop(Ebmax).By contrast,Egmax decreases in different degrees at high We and BoE,respectively.There is little difference between Egmax and Ebmax in the position and the occurring time.The influence mechanism on the maximum electric field and discharges and the relationship between discharges induced by the pendant water drop and rain flashover are discussed.

Synthesis and Characterization of Poly（ε-caprolactone-co-δ- valerolactone） with Pendant Carboxylic Functional Groups

In this paper, aliphatic polyesters functionalized with pendant carboxylic groups were synthesized via several steps. Firstly, substituted cyclic ketone, 2-（benzyloxycarbonyl methyl）cyclopentanone （BCP） was prepared through the reaction of enamine with benzyl-2-bromoacetate, and subsequently converted into the relevant functionalized 6-valerolactone derivative, 5-（benzyloxy carbonylmethyl）-δ-valerolaetone （BVL） by the Baeyer-Villiger oxidation. Secondly, the ring-opening polymerization of BVL with ε-caprolactone was carried out in bulk using stannous octoate as the catalyst to produce poly（ε-caprolactone-co-δ-valerolactone） bearing the benzyl-protected carboxyl functional groups [P（CL-co-BVL）]. Finally, the benzyl-protecting groups of P（CL-co-BVL） were effectively removed by H2 using Pd/C as the catalyst to obtain poly（ε-caprolactone-co-δ-valerolactone） bearing pendant carboxylic acids [P（CL-co-CVL）]. The structure and the properties of the polymer have been studied by Nuclear Magnetic Resonance （NMR）, Fourier Infrared Spectroscopy （FT-IR） and Differential Scan Calorimetry （DSC） etc. The NMR and FT-IR results confirmed the polymer structure, and the 13C NMR spectra have clearly interpreted the sequence of ε-caprolactone and 5-（benzyloxycarbonylmethyl）-δ-valerolactone in the copolymer. When the benzyl-protecting groups were removed, the aliphatic polyesters bearing carboxylic groups were obtained. Moreover, the hydrophilicity of the polymer was improved. Thus, poly（ε-caprolactone-co-δ-valerolactone） might have great potential in biomedical fields.

Experimental and thermal stress investigation on side wall deformation at the pendent convective pass in a utility boiler

An experimental investigation is performed on side wall deformation at the pendant convective pass (PCP) in a 300 MW and a 600 MW utility boiler. The temperature distributions are measured on the side wall areas of the water-cooled wall, the PCP and the horizontal convective pass (HCP) in the two utility boilers. These experiments show that there are great temperature differences in the side wall areas during the startup process in both utility boilers. These temperature differences can reach 80～150 °C with the side wall temperature in the PCP area higher than those in the water-cooled wall and the HCP. The highest temperature in the PCP is close to the flue gas side temperature at the same position in the horizontal flue gas pass. Thermal stress analyses are conducted in the side wall areas in the water-cooled wall, the PCP and the HCP with the software ANSYS. The results show that, at great temperature differences, the PCP side wall undergoes negative thermal stresses that exceed the yield strength causing deformation in the PCP side wall.

Reactive poly(divinyl benzene-co-maleic anhydride) nanoparticles:Preparation and characterization

Polymeric nanoparticles（NPs）have drawn great interest in the past few years due to their potential applications in the felds of biomedical and optical technologies.However,it is still a challenge to prepare functional polymeric NPs,especially for particle diameters smaller than 50 nm.In this work,we demonstrate a one-pot method to fabricate reactive poly（divinyl benzene-co-maleic anhydride）NPs（PDVBMAH NPs）through a self-stable precipitation polymerization process.The size and morphology of these PDVBMAH NPs were characterized in detail by scanning electronic microscopy,and their chemical structure was determined by IR.The results showed that these NPs were highly cross-linked and their diameter was about 30 nm with narrow distribution.Additionally,the DVB and MAH endow the NPs with reactive surface anhydride and pendant vinyl groups,and these particles could be further functionalized through reaction of these groups.A plausible pathway was proposed for the formation of PDVBMAH NPs.