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The formation of C–S bonds using cheap, stable and odorless sulfonyl chlorides and widely sourced and less toxic alcohols with the assistance of ADDP is reported.

A type of grafted acrylate copolymer resins, containing 3‐oxo‐N‐allyl‐1,2‐benzisothiazole‐2(3H)‐carboxamide monomer and heterocyclic monomers, was synthesized through the copolymeri‐ zation of methyl methacrylate (MMA) and butyl acrylate (BA) with functional monomers. The structures of the monomers and copolymers were validated by infrared (IR) and 1H nuclear magnetic resonance (NMR) spectroscopies. The inhibitory activities of the copolymers on algae, bacteria, and barnacle larvae were measured, and the antifouling potencies against marine macrofouling organisms were investigated. The results showed that the grafted resin had significant inhibitory effects on the growth of three marine algae (Isochrysis galbana, Nannochloropsisoculata, and Chlorella pyrenoidosa), and three bacteria (Vibrio coralliilyticus, Staphylococcus aureus,and Vibrio parahaemolyticus). The target copolymers also showed excellent inhibition of the survival of barnacle larvae. Additionally, the release rate of the antifoulant and the results of the marine field tests indicated that the grafted copolymers had outstanding antifouling potency against the attachment of marine macrofouling organisms., Grafted acrylate copolymer resins containing 3‐oxo‐N‐allyl‐1,2‐benzisothiazole‐2(3H)‐carboxamide monomer and heterocyclic monomers, have been prepared via copolymerization of methyl methacrylate and butyl acrylate with functional monomers. The structures of the monomers and copolymers were validated by infrared and 1H nuclear magnetic resonance spectroscopies. The inhibitory activities of the copolymers on algae, bacteria, and barnacle larvae were measured, and the antifouling potencies against marine macrofouling organisms were investigated.

In order to find a new type of antifouling coating with higher biological activity and more environmental protection, heterocyclic compounds and benzisothiazolinone were introduced into acrylic resin to prepare a new type of antifouling resin. In this study, a series of grafted acrylic resins simultaneously containing benzoisothiazolinone and heterocyclic monomers were prepared by the copolymerization of an allyl monomer with methyl methacrylate (MMA) and butyl acrylate (BA). Inhibitory activities of the copolymers against marine fouling organisms were also investigated. Results revealed that the copolymers exhibit a clear synergistic inhibitory effect on the growth of three seaweeds: Chlorella, Isochrysis galbana and Chaetoceros curvisetus, respectively, and three bacteria, Staphylococcus aureus, Vibrio coralliilyticus and Vibrio parahaemolyticus, respectively. In addition, the copolymers exhibited excellent inhibition against barnacle larvae. Marine field tests indicated that the resins exhibit outstanding antifouling potency against marine fouling organisms. Moreover, the introduction of the heterocyclic group led to the significantly enhanced antifouling activities of the resins; the addition of the heterocyclic unit in copolymers led to better inhibition than that observed in the case of the resin copolymerized with only the benzoisothiazolinone active monomer.

Random-pattern skin flap necrosis limits its application in the clinic. It is still a challenge for plastic surgeons. Catalpol is an effective ingredient extracted from Rehmannia glutinosa, which is reported to promote angiogenesis and protect against ischemic cerebral disease. The aim of our experiment is to assess whether catalpol can facilitate random flap survival and the underlying mechanisms. Male “McFarlane flap” rat models were employed to explore the protective effects of catalpol. The range of necrosis in the flap was calculated 7 days after the models were established. The flap specimens were harvested for further experiments, including angiogenesis, apoptosis, oxidative stress, and autophagy evaluation. Catalpol-treated group promoted the average survival area of the flap than that in the control group. Based on immunohistochemical staining, Western blotting, and ROS detection, we found that catalpol significantly reduces oxidative stress and apoptosis and increases angiogenesis. Hematoxylin and eosin (H&E) staining and laser Doppler images further clarified the enhancement of angiogenesis after catalpol treatment. The impact of catalpol in flap was switched by using 3-methyladenine (3MA), proving the important role of autophagy in curative effect of catalpol on skin flaps. Importantly, the ability of catalpol to regulate autophagy is mediated by the activation of sirtuin 1 (SIRT1) based on its high affinity for SIRT1. Our findings revealed that catalpol improved the viability of random skin flaps by activating SIRT1-mediated autophagy pathway.

A new protocol for Pd(OAc)2-catalyzed reactions of different benzyl bromides and various arylboronic acids has been developed to form functionalized benzyl phenyl ethers. This method represents the first instance where arylboronic acid is used as a reaction substrate for benzyl phenyl ether synthesis with H2O2 as the green oxidant under atmospheric oxygen and pure H2O as an environmental friendly solvent without the requirement for phosphine- and N-based ligands, remarkable functional group tolerance, and considerable yield.

Objective: To investigate therapeutic effects of Widman flap operation on treating severe chronic periodontitis and influence of it on inflammatory factors. Methods: A total of 129 cases of patients with severe chronic periodontitis treated in the dental department of our hospital from Nov2014 to Mar2016 were selected as investigate subjects. They were randomly divided to be 63 cases of control group and 66 cases of observation group. For control group, basic treatment was provided. For observation group, improved Widman flap operation was provided. Compared with the effects between two groups of patients, and analyzed the variation of each inflammatory factor before and after treatment. Results: Before treatment, no significant difference showed on PLI, SBI, CAL, PD indexes between two groups of patients. 6 weeks after treatment, PLI, SBI, PD in observation group were significantly decreased comparing with prior treatment, and PLI, SBI were significantly lower than control group at the same phase. 12 weeks after treatment, PLI in control group were significantly decreased comparing with prior treatment; PLI, SBI, CAL, PD in observation group were significantly decreased comparing with prior treatment, and were significantly lower than control group at the same phase. Before treatment, no significant difference showed on IL-1β, IL-6, TNF-α, CRP levels between two groups of patients. After treatment, 4 inflammatory factors in control group showed no significant variation comparing with the same group before treatment, 4 inflammatory factor levels in observation group were significantly lower than which before treatment, IL-1β, IL-6, TNF-α were significantly lower than control group at the same phase. Conclusion: Improving extent of modified Widman flap operation to periodontal indexes and inflammatory factors in patients with severe periodontitis were better than the basic treatment for control group. It could be a choice for treatment of severe periodontitis.

Purpose. To assess the impact of sinogram-affirmed iterative reconstruction (SAFIRE) on risk category for coronary artery disease by combining coronary calcium score measurement and coronary CT angiography (CCTA). Materials and Methods. Eighty-nine patients (64.0% male) older than 18 years (64.4±10.3 years) underwent coronary artery calcium scanning and prospectively ECG-triggered sequential CCTA examination. All raw data acquired in coronary artery calcium scanning were reconstructed by both filtered back projection (FBP) and SAFIRE algorithms with 5 different levels. Objective image quality and calcium quantification were evaluated and compared between FBP and all SAFIRE levels by the Sphericity Assumed test or Greenhouse-Geisser ε correction coefficient. Coronary artery stenosis was assessed in CCTA. Risk categories of all patients and of the patients with coronary artery stenosis in CCTA were compared between FBP and all SAFIRE levels by the Friedman test. Results. The reconstruction protocol from traditional FBP to SAFIRE 5 was associated with a gradual reduction in CT value and image noise (P<0.001) but associated with a gradual improvement in the signal-to-noise ratio (P<0.001). There was a gradual reduction in coronary calcification quantification (Agatston score: from 73.5 in FBP to 38.1 in SAFIRE 5, P<0.001) from traditional FBP to SAFIRE 5. There was a significant difference for the risk category between FBP and all levels of SAFIRE in all patients (from 3.5 in FBP to 3.2 in SAFIRE 5, P<0.001) and in the patients with coronary artery stenosis in CCTA (from 4.0 in FBP to 3.6 in SAFIRE 5, P<0.001). Conclusions. SAFIRE significantly reduces coronary calcification quantification compared to FBP, resulting in the reduction of risk categories based on the Agatston score. The risk categories of the patients with coronary artery stenosis in CCTA may also decline. Thus, SAFIRE may lead risk categories to underestimate the existence of significant coronary artery stenosis.

A direct and highly stereoselective approach for the synthesis of Z-alkenyl-pyranoindoles had been developed by utilizing Rh(II)-catalyzed intramolecular cyclization of N-sulfonyl-1,2,3-triazoles with indole derivatives. A variety of pyranoindoles were obtained in 44–93% yields. Moreover, a more convenient synthesis of pyranoindoles starting from terminal alkyne was realized via a Cu–Rh sequentially catalyzed one-pot cascade reaction.

Summary: Two types of cascade nuclear track filters have been developed: (1) cascade filter made of polypropylene (PP) fiber membrane as preliminary filter and nuclear track membrane (NTM) as terminal filter; (2) Nylon tortuous-pore membrane as preliminary filter and NTM as terminal filter. Removal of solid particles by the cascade filters has been investigated. The solid particles studied include glass shards from broken ampoules and rubber fragments from rubber covers (plugs) of medical bottles. When an ampoule containing medicine is broken by emery wheel and by hands, large number of glass shards are produced and fall into the medicine. When a rubber cover is punctured by syringe needle, large number of rubber fragments are produced by friction between rubber and needle. The investigation shows that fiber or tortuous membranes alone usually cannot completely remove the microscopic particles due to existence of large gaps in the structure of the two common membranes. Nuclear track membranes alone and their cascade filters are superior to remove all solid particles bigger than the pore size of the track membrane. Removal efficiency for solid particles and flow rate of injections through the cascade filters have been calibrated and shown that both features above fulfill the requirements of Chinese regulations. The two types of cascade filters have been accepted for use in Chinese hospitals. Keywords: Nuclear track membrane, Polypropylene fiber membrane, Nylon tortuous-pore membrane, Nuclear track cascade filter, Glass shards from broken ampoules, Rubber fragments from bottle covers, Removal efficiency of solid particles, Flow rate of injections

Industrial solid waste refers to all solid waste derived from industrial processes. Industrial solid waste, on the one hand, may lead to environmental risk and safety issue; on the other hand, contains valuable recyclable resources. Taking copper slag as a case study, the life cycle environmental and economic performance of recycling process were analyzed by using life cycle assessment and life cycle costing approaches. The functional unit was defined as the recycling of 1 ton of copper slag. The results showed that the process of production of cement after floatation was the optimal scenario for copper slag recycling, and its life cycle impact and life cycle cost were-67.22 Pt and-479.28 yuan, respectively. Specifically, the dominant environmental impact category of copper recycling process was respiratory (inorganic). In addition, raw material, fuel and power, equipment depreciation and transportation contributed to the life cycle cost in descending order of their proportion.

Tolerance analysis plays an important role at the stage of product design and has great influences on the assembly quality and manufacturing costs. A positioning mechanism composed of two parts with cylindrical and planar junction is chosen for studying the influences of datum precedence on functional tolerance analysis. For different cases, the tolerance specification is specified with ISO tolerance language and the analysis line method is applied to obtain the analytical expression between the possible displacement on functional feature and geometric deviation on each part. The results for different datum precedence are summarized in this paper.

This paper reviews two major models (Small Displacement Torsor, Deviation and Clearance Domain) for 3D functional tolerance analysis and compares them. The underlying mathematical representation of geometric tolerances can be classified as inequalities and multi-variate region. The corresponding algebraic or geometric tolerance propagation mechanism of each model is briefly introduced for worst-case and statistical tolerancing. Through a comprehensive comparison of these models, this paper gives some suggestions for choosing the appropriate method for a given tolerancing problem.

Roundness error evaluation software is developed based on two-dimensional circle fitting with least-squares method based on nonlinear optimization with constraints. The local derivative-free optimization algorithms of NLopt can solve nonlinear constraint problems by combining with augmented Lagrangian algorithm. The fitting precision and convergence time of each algorithm are analyzed by calculating the fitting results with same test data to find its advantages and disadvantages. It is shown that each algorithm has different behaviors from others on performance and stability. This work provides a good basis for choosing the appropriate algorithm for roundness error evaluation.

Tolerance analysis plays an important role at the stage of product design and has great influences on the assembly quality and manufacturing costs. For each ending point on the functional feature, the displacement transfer relationship is influenced by the clearance between the two parts and the tolerances of each part. With regard to functional tolerance accumulation for the simple assembly, the tolerance analysis of a complex mechanism with three parts is conducted based on the analysis line method. The rules for the functional tolerance analysis process will be summarized in this paper.

The dynamic modeling method for parallel robot based on the principle of virtual work and equivalent tree structure is proposed by taking off the platform and the chains as well as degenerating parallel robot into a tree structure, the closed-form solutions for the inverse and forward dynamics models of parallel robot are derived. The method is applied on kinematics and dynamics analysis of a representative 3-RRR spherical parallel robot.

Background Survival benefits of mild hypothermia in animals suffering from uncontrolled hemorrhagic shock (HS) may be influenced by trauma severity. We hypothesized that mild hypothermia would improve early outcomes based on our rabbit model of severe traumatic HS. Materials and methods Fifty male New Zealand rabbits weighing between 1.6 and 2.2 kg were randomized into one of the five groups: group 1 (sham), group 2 (37°C/80 mm Hg), group 3 (37°C/40 mm Hg), group 4 (34°C/80 mm Hg), and group 5 (34°C/40 mm Hg). Under urethane anesthesia, animals that suffered fractures and uncontrolled HS received prehospital fluid resuscitation (aggressive or limited) with temperature controlled at normothermia or mild hypothermia, hemostasis, and hospital resuscitation followed by observation. Results Mild hypothermia significantly improved cardiac systolic function and decreased lung wet-to-dry weight ratios and total injury score compared with normothermia. Group 5 manifested the best results in lung injury. The decreased base excess and pH and increased lactate levels during HS and limited fluid resuscitation were not exacerbated by mild hypothermia. Electrolytes including potassium and calcium and blood glucose levels as well as coagulation were not significantly influenced after mild hypothermia treatment. Seven-hour survival in the hypothermic groups was higher than that in the normothermic groups, although there was no significant difference in survival between groups 5 and 3. Conclusions Therapeutic mild hypothermia improves early outcomes through improving lung and cardiac performance without causing evident homeostasis disturbances in the rabbit model of traumatic uncontrolled HS. Animals may benefit most under the combination treatment with mild hypothermia and limited fluid resuscitation.

Twenty-one novel compounds were synthesized from the benzo[d]isothiazole-3(2H)-one and aromatic acid, the structures were identified by means of 1H NMR, IR, EA. The intro antibacterial experiment was carried out to evaluate the activities against antibacterial and the marine hanging plate experiment was also carried out to evaluate the activities against marine fouling organism. The results showed that all the compounds were active against the six bacterials, with an inhibiting rate of 90% at the concentration of 32 µg/ml against Gram-positive bacterials, and the antifouling paints couldn’t be attached by marine fouling organisms in the marine environment for more than 3 months.

A direct and highly stereoselective approach for the synthesis of Z-alkenyl-pyranoindoles had been developed by utilizing Rh(II)-catalyzed intramolecular cyclization of N-sulfonyl-1,2,3-triazoles with indole derivatives. A variety of pyranoindoles were obtained in 44–93% yields. Moreover, a more convenient synthesis of pyranoindoles starting from terminal alkyne was realized via a Cu–Rh sequentially catalyzed one-pot cascade reaction.

Manipulating large numbers of a variety of particles/wires is essential for many lab-on-a-chip technologies. Here we generate a planar array of optofluidic vortices with photothermal gradients from an easy-fabricated graphene oxide (GO) heater to achieve high-throughput and multiform manipulation at low excitation power and low loss. As a tweezer, each vortex can rapidly capture and confine particles without restrictions on shapes and materials. The stiffness of the confinement is easily tuned by adjusting the vortex dimension. As a motor, it can actuate any traps to persistently rotate/spin in clockwise or anti-clockwise mode. As a high-performance “workshop”, this work lays the groundwork for various self-assembly ranging from colloid-based clusters, chains, capsules, shells, and ultra-thin films, through particles' surface modification and fusion, to nanowires-based architectures. Furthermore, we can create multiple vortex arrays through fabricating an array of heaters, which enables a wider range of manipulation and distributed operations all on a chip.

Tolerance analysis plays an important role in the stage of product design and has great influences on the product assembly quality and manufacturing costs. Two major methods are used for three-dimensional functional tolerance analysis, which are small displacement torsor and analysis line. A positioning mechanism with two parts is presented for tolerance accumulation calculation. Through the comparison of these two methods on computation processes and results, analysis line method can establish the explicit relationship between the functional requirement and the tolerances of the influential part, which allows finding the accumulation results in the worst-case and statistical conditions. However, it requires the determination of transfer relationship case by case. For small displacement torsor model, it permits a set of inequalities to express the tolerance zones, which yields a linear programming problem. It is applicable to different tolerance chains for its general characteristic. However it is adopted only for the worst-case analysis and requires more computation time.

Recently the parallel manipulator with less DOFs has attracted industry and academia, but the research on its dynamics is still an open problem. In this paper, the inverse dynamic of a spatial parallel manipulator with two translational degrees of freedom and one rotational degree of freedom is studied based on the Newton-Euler approach. The kinematics analysis is firstly performed in a closed form. The inverse dynamic equation of this manipulator is formulated by using the Lagrange multiplier approach and choosing the Cartesian position and orientation as the generalized coordinates. Finally a numerical example is given for the kinematic and dynamic simulation of this manipulator. The model will be useful to improve the design of the mechanical components and the control algorithm.

W/C ratio and the quantity of fly ash added have obvious influence on creep of high performance concrete. Effect of different quantities of fly ash on creep of high performance concrete of different W/C ratios used in bridge is studied in this research whose results reflect that creep value reduces along with reduction of W/C ratio at a certain quantity of fly ash added. Adding fly ash restrains creep on the whole, however, the degree depends on the quantity of fly ash added. Creep value of high performance concrete mixed with class-I fly ash at blend ratio of 12~40% is lower than that of standard concrete and fly ash at blend ratio of 18% has the best effect. Creep value in 365d is 51% of that of standard concrete at fly ash blend ratio of 18%, while at fly ash blend ratio of 40%, creep value in 365d is lower than that of standard concrete but higher than that of concrete at other blend ratios. It is generally considered that inhibition of creep of high performance concrete begins to fall beyond blend ratio of 30%.

Ethylenediamine-functionalized activated carbon anchored palladium catalyst was prepared via grafting ethylenediamine onto chemically modified activated carbon, followed by the reaction with palladium chloride and then the reduction with potassium borohydride. Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy results indicated that palladium immobilized on the carrier via coordination bond in this catalyst. Transmission electron microscopy images showed that the supported palladium is in the form of near spherical particles smaller than 10 nm diameter and evenly dispersed on the surface of the carrier. This catalyst was applied for the Heck reaction of aryl halides with olefins. The influences of solvents, bases, reaction temperatures and times on catalytic property of the catalyst were investigated by using the coupling of iodobenzene and styrene as a probe reaction. By varying the combination of aryl halides and olefins, this catalyst showed effective catalytic activities to produce corresponding coupling products with moderate to excellent yields. Moreover, it can be recovered by simple filtration and reused several times without significant loss of activity and selectivity.

A series of fluorescence compounds, 4-benzofuranyl-1,8-naphthalimides, were prepared through cycloaddition reaction from 4-ethynyl-1,8-naphthalimides and o-iodophenols which catalyzed by a Pd(PPh3)2Cl2 / CuI system under mild conditions. The intermediate material, 4-ethynyl-1,8- naphthalimide, was synthesized from 4-bromo-1,8- naphthalimide and trimethylsilyl- acetylene. The absorption and fluorescence spectra of 4-benzofuranyl-1,8- naphthalimides were studied and the quantum yields were measured. The maximum UV/vis absorption spectra were in the range of 375-400 nm and the maximum emission spectra were in the range of 470-510 nm. The electro- luminescent properties were also mensurated through a doped electroluminescent device which contains 1% 1,8-naphthalimides and 99% CBP (4,4'-N,N'-dicarbazole-biphenyl), It’s shown the maximum brightness reached 3700 cd/ m2 at 22.5V.

This paper presents an experimental study on the dynamics of flexible parallel robots. First, a theoretical study on the dynamic modeling and numerical solution of parallel robots with flexible links is introduced briefly. Second, the experiment setup that includes the test-bed mechanism of a 3-RRR flexible parallel robot and the hardware and software structures of a control system are then developed. Finally, the experimental study is presented to show the good agreement between the theoretical analysis and experimental results.

The internal recycling process of BOF slag which is one of the huge solid wastes from iron and steel industry was emphasized. Based on the four scenarios of different internal recycling strategies for BOF slag, life cycle assessment (LCA) as a valuable tool for industrial solid waste management was applied to analyze the contribution to reducing environmental impacts and resources burdens for each scenario. The global warming potential (GWP) results of the four scenarios show that the scenario which performs best in carbon reduction cuts off 14.2% of GWP impacts of the worst scenario. The results of this study show that the optimized internal recycling process of BOF slag can improve the environmental performance of crude steel. It is important to assess and choose an appropriate strategy to recycle BOF slag from LCA perspective to reduce the environmental impacts and resource burdens as much as possible.

Aiming at the wide application of technological design in three-dimensional CAD software, while the technological dimension chain’s calculation is completed in the two-dimensional process sketch still. A sort of method of calculating technological dimension chain was put forward, which is based on three-dimensional process model. Three-dimensional process model is created through the process of technological design by introducing the concept of three-dimensional process model, and then, the information of process dimension is extracted from the three-dimensional process model and a tree oriented process dimension structure is established. On the basis of the above, we can proceed with technological dimension chain’s integrated calculation and analysis, redistributing the process dimension and its corresponding allowance dimension and tolerance. It will offer more reasonable and reliable process parameters to the technologists in the design of process route, and also effectively solve the problems of the technological dimension chain’s calculation involving to CAPP system in the environment of three-dimensional CAD software.

International audience; This paper depicts a new CAT (Computer Aided Tolerancing) system called Quick GPS (Geometrical Product Specification), for assisting the designer when specifying the functional tolerances of a single part included in a mechanism, without any required complex function analysis. The mechanism assembly is first described through positioning table formalism. In order to create datum reference frames and to respect assembly requirements, an ISO-based 3D tolerancing scheme is then proposed thanks to a set of rules based on geometric patterns and TTRS (Technologically and Topologically Related Surfaces). Since it remains impossible to determine tolerance chains automatically, the designer must impose links between the frames. The CAT system we developed here proposes ISO based tolerance specifications to help ensure compliance with the designer's intentions saving on time and eliminating errors. This paper will detail both the set of tolerancing rules and the designer's approach. The Quick GPS system has been developed in a CATIA V5 environment using CATIA VBA and CATIA CAA procedures.

Battery Electric Bus (BEB) has become one of prior options of urban buses for its "zero emission" during the driving stage. However, the environmental performance of electric buses is affected by multi-factors from the point of whole life cycle. In practice, carrying capacity of BEB and power generation structures can both implement evident effects on the energy consumption and pollutants emission of BEB. Therefore, take the above factors into consideration, in this article, Life Cycle Assessment is employed to evaluate the energy conservation and emissions reduction benefits of BEB. Results indicate that, travel service is more reasonable as the functional unit, rather than mileage, since the carrying capacity of BEB is 15% lower than the diesel buses. Moreover, compared with diesel buses, the energy conservation and emissions reduction benefits of battery electric buses are all different due to different regional power structures. Specifically, the energy benefits are 7. 84%, 11. 91%, 26. 90%, 11. 15%, 19. 55% and 20. 31% respectively in Huabei, Huadong, Huazhong, Dongbei, Xibei and Nanfang power structure. From the point of comprehensive emissions reduction benefits, there is no benefit in Huabei power structure, as it depends heavily on coal. But in other areas, the comprehensive emissions reduction benefits of BEB are separately 3. 46%, 26. 81%, 1. 17%, 13. 74% and 17. 48% in Huadong, Huazhong, Dongbei, Xibei and Nanfang. Therefore, it suggests that, enlargement of carrying capacity should be taken as the most prior technology innovation direction for BEB, and the grids power structure should be taken into consideration when the development of BEB is in planning.