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Shen C.,Hangzhou Normal University | Shen C.,Zhejiang Shuren University | Zhang P.,Hangzhou Normal University | Sun Q.,National University of Singapore | And 5 more authors.
Chemical Society Reviews | Year: 2015

The development of mild and general methods for C-S bond formation has received significant attention because the C-S bond is indispensable in many important biological and pharmaceutical compounds. Early examples for the synthesis of C-S bonds are generally limited to the condensation reaction between a metal thiolate and an organic halide. Recent chemical approaches for C-S bond formation, based upon direct C-H bond functionalization and decarboxylative reactions, not only provide new insights into the mechanistic understanding of C-S coupling reactions but also allow the synthesis of sulfur-containing compounds from more effective synthetic routes with high atom economy. This review intends to explore recent advances in C-S bond formation via C-H functionalization and decarboxylation, and the growing opportunities they present to the construction of complex chemical scaffolds for applications encompassing natural product synthesis, synthetic methodology development, and functional materials as well as nanotechnology. © The Royal Society of Chemistry 2015.


Chen W.Q.,Zhejiang Shuren University | Lou D.P.,Zhejiang Sanhe Food Science and Technology Co.
Advanced Materials Research | Year: 2014

Bamboo shaving is a by-product of bamboo industry, often be discarded or incinerated. In this work, sodium carboxymethyl cellulose (CMC) was prepared from pretreated bamboo shaving as raw material, while the main reaction conditions affecting product properties such as pretreated method, alkalization temperature and time, etherified temperature and time were studied. The results showed that the optimized pretreated conditions for bamboo cellulose were soaked in 15% NaOH at 1:8 (w/v) ratio of cellulose to solvent for 1 h at 95°C, The content of α-cellulose reach to 94.25%. The optimized reaction conditions for CMC synthesis were alkalified at 30°C for 70 min and etherified at 55°C for 90min; afterwards, temperature was kept at 70°C for 10min. Under these conditions, viscosity of 1% CMC aqueous solution was above 260 mPa·s, degree of substitution (DS)≥0.8, and content of chloride and moisture were less than 1.2% and 10% respectively. © (2014) Trans Tech Publications, Switzerland.


Shen C.,Zhejiang Shuren University | Shen C.,Hangzhou Normal University | Xu J.,Hangzhou Normal University | Yu W.,Hangzhou Normal University | Zhang P.,Hangzhou Normal University
Green Chemistry | Year: 2014

Aryl sulfones were synthesized using a highly active and easily recoverable heterogeneous Cu catalyst which was prepared by simply stirring an aqueous suspension of chitosan in water with copper salts. The chitosan@copper catalyst catalyzed the coupling reactions of aryl halides with sodium sulfinates to readily give the corresponding sulfones in good to excellent yields. The highly active catalyst can be reused many times without losing its catalytic activity. In addition, by using this protocol, the marketed drug zolimidine (antiulcer) could be synthesized easily. This journal is © the Partner Organisations 2014.


Xing L.,Zhejiang Shuren University
Material Science and Environmental Engineering - Proceedings of the 3rd annual 2015 International Conference on Material Science and Environmental Engineering, ICMSEE 2015 | Year: 2016

With the development of marine economy, a lot of marine buildings and port structures need to be built. So amount of concrete is needed. If these buildings were built by the concretes with sea sand and sea water instead of the traditional concretes, raw materials can be obtained locally and time and cost can be saved. Based on the above considerations, the workability and strength were studied with the changing of the content of salinity and shells. The results show that with the increase of salinity, the slump is increased and the mobility is enhanced, but the cohesion is deteriorated; with the increasing content of shells, the slump is reduced, water retention is worse. The strength of concrete with sea sand and sea water is not vary with the changing of the content of the salinity and shells, but the early strength has declined comparing with conventional concrete, dropping by about 20 percent. With the increase of age, the strength of two kinds of concretes is quite. © 2016 Taylor and Francis Group, London.


Lai X.-J.,Zhejiang Shuren University | Cai X.-O.,Zhejiang Shuren University
Zeitschrift fur Naturforschung - Section A Journal of Physical Sciences | Year: 2011

The exact chirped soliton-like and quasi-periodic wave solutions of the (3+1)-dimensional generalized nonlinear Schrödinger equation including linear and nonlinear gain (loss) with variable coefficients are obtained detailedly in this paper. The form and the behaviour of solutions are strongly affected by the modulation of both the dispersion coefficient and the nonlinearity coefficient. In addition, self-similar soliton-like waves precisely piloted from our obtained solutions by tailoring the dispersion and linear gain (loss). © 2011 Verlag der Zeitschrift für Naturforschung, Tübingen.


Xu D.,Zhejiang Shuren University | Li C.,Zhejiang University | Wen Y.,Zhejiang University | Liu W.,Zhejiang University
Environmental Pollution | Year: 2013

The use of earthworms as a sublethal endpoint has significantly contributed to the ecological risk assessment of contaminated soils. Few studies have focused on the potential toxicity of PFOS to earthworms in the soil. In this work, artificial soils were tested, and contact filter paper studies were used. The results showed that earthworm growth was generally inhibited. The antioxidant activities of the enzymes superoxide dismutase, peroxidase, catalase and glutathione peroxidase were initially activated and then inhibited. Reduced glutathione content was observed, and malondialdehyde content was elevated over the duration of the exposure. These results suggested that PFOS induced oxidative stress in earthworms. In addition, the values of olive tail moment, tail DNA% and tail length using SCGE showed similar frequency distributions and increased with increases in the PFOS concentration. These results suggest that all concentrations of PFOS cause DNA damage. © 2012 Elsevier Ltd. All rights reserved.


Shen C.,Zhejiang Shuren University | Shen C.,Hangzhou Normal University | Zhang P.-F.,Hangzhou Normal University
Current Organic Chemistry | Year: 2013

In recent years, asymmetric reactions catalyzed by the carbohydrate-based catalysts are the most intensively studied as they have been recognized as versatile starting materials for chiral auxiliaries, reagents, ligands and organocatalysts. The design and finetuning of carbohydrate-based catalysts is facilitated by the multiple functional groups present within this class of compounds. This strategy has provided unique ligand moieties which combine the performance of "privileged catalysts" with increased flexibility and accessibility. With the development of sugar-based ligands in selective catalysis, D-glucosamine has been selected as a cheap and readily available chiral scaffold for the synthesis of a series of novel ligands and organocatalysts. D-glucosamine-derived chiral catalysts has gained continuous increasing interest in asymmetric reactions. In this review, key development of asymmetric reactions catalyzed by Dglucosamine- derived chiral catalysts is summarized. © 2013 Bentham Science Publishers.


Zhou Z.-S.,Zhejiang Shuren University | He X.-H.,Zhejiang Institute of Geology
Tetrahedron Letters | Year: 2010

A novel and convenient catalytic method for phosphoryloxylactonization of pentenoic acids is available: the cyclization of 4-pentenoic acids with phosphates using iodobenzene as a recyclable catalyst in combination with m-chloroperbenzoic acid as the terminal oxidant was easily carried out in CF3CH2OH at room temperature, giving phosphoryloxylactons in good yields, some of them had two diastereoisomers. © 2010 Elsevier Ltd. All rights reserved.


Cai X.-o.,Zhejiang Shuren University
Optik | Year: 2010

Based on the whole process of recording and reconstruction of digital holography, we study the formation causes of speckle noise in the reconstructed image and its characteristics. And we reach the conclusions that the little hologram aperture diffraction aggravates the speckle noise and the speckle noise in the reconstructed image is a kind of multiplicative noise. Serving as the basis of these features, we propose the reduction technique for speckle noise. Firstly, we set an appropriate aperture function matching the recording parameter and an aperture size of hologram and deconvolve the reconstructed image of the hologram with it. Secondly, we converted the multiplicative noise into additive noise by means of homomorphic transform and realize the separation of signal and noise. Thirdly, we applied the Wiener filtering to reduce the additive noise. Finally, we carried out the inverse transformation. The proposed reduction technique is illustrated with experimental results. Therefore, the paper offers a brand-new thought and practical way of reducing the speckle noise in the reconstructed image of digital holography. © 2008 Elsevier GmbH. All rights reserved.


Lai X.-J.,Zhejiang Shuren University
Communications in Theoretical Physics | Year: 2011

The exact chirped soliton-like and quasi-periodic wave solutions of (2 + 1)-dimensional generalized nonlinear Schrödinger equation including linear and nonlinear gain (loss) with variable coefficients are obtained detailedly in this paper. The form and the behavior of solutions are strongly affected by the modulation of both the dispersion coefficient and the nonlinearity coefficient. In addition, self-similar soliton-like waves precisely piloted from our obtained solutions by tailoring the dispersion and linear gain (loss). © 2011 Chinese Physical Society and IOP Publishing Ltd.

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