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Chinese Chemical Letters 2003年第10期14卷 1012-1014页

作者： Jian Kui ZHAO, yan guang wang Department of Chemistry, Zhejiang University, Hangzhou 310027 Department of Chemistry Zhejiang University

A general synthesis of diaryl ethers via coupling of aryl halides with substituted phenoxytrimethylsilane in the presence of TBAF is described. The protocol is simple and mild, and gives good to excellent yields.

关键词： Diaryl ether TBAF aryl halide phenoxytrimethylsilane.

Comparison of IOL-Master 700 and IOL-Master 500 biometers in ocular biological parameters of adolescents

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International Journal of Ophthalmology(English edition) 2021年第7期14卷 1013-1017页

作者： Qiang Shi guang-yan wang Yu-Hong Cheng Cheng Pei Department of Ophthalmology the First Affiliated Hospital of Medical CollegeXi’an Jiaotong UniversityXi’an 710061Shaanxi ProvinceChina

AIM:To compare the differences and consistency of IOL-Master 700 biometers applying swept optical coherence tomography with the conventional IOL-Master 500 applying partial coherence interference in terms of the ocular biological parameters in adolescents with ***:A total of 110 adolescents(110 eyes)with ametropia were collected,including 55 males and 55 females;age 10.69±2.81 *** biological measurements were taken by IOL-Master 700 and IOL-Master 500 respectively to obtain biological parameters including axial length(AL),mean corneal anterior surface keratometry(K_(m)),anterior chamber depth(ACD),and horizontal corneal diameter(WTW).Paired t-test was used to compare the differences between the two *** intra-group correlation coefficient(ICC)and the Bland-Altman analysis were used to evaluate the consistency of parameter measurements between the two instruments for the four biological ***:Statistical analysis showed that there was no significant difference in the K_(m)value measured by IOL-Master 700 and IOL-Master 500(t=-1.644,P=0.116).The average differences of the AL,ACD,and WTW distances between the two instruments are 0.028,0.101 and 0.064 mm respectively,and the differences are statistically significant(t=2.644,12.505,3.911,P<0.001).The consistency study results indicated high correlation in the measurement of AL,K_(m),ACD and WTW between the two instruments(ICC=0.994,0.873,0.927,0.912).CONCLUSION:The novel biometric instrument IOL-Master 700 makes no difference with IOL-Master 500 in the measurement of K_(m).There are some differences in the values of AL,ACD,and ***,the two instruments show good consistency in these four biological *** measured values of K_(m)are interchangeable between the *** two types of biometrics can be used as mutual reference in consideration of that the differences in AL,ACD,and WTW measurements are not sufficient to produce clinically meaningful differen

关键词： myopia adolescents axial length IOL-Master 700 IOL-Master 500

An Efficient and Chemoselective Deprotection of tert-Butyldimethyl-silyl Protected Alcohols Using SnCl_2·2H_2O as Catalyst

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Chinese Chemical Letters 2004年第12期15卷 1430-1432页

作者： Jun HUA Zhi Yong JIANG yan guang wang Department of Chemistry, Zhejiang University, Hangzhou 310027 Department of Chemistry Zhejiang University

An efficient and selective method for the deprotection of primary alcoholic tert-butyl-dimethylsilyl (TBS) ethers using SnCl_2·2H_2O as catalyst is described. The reaction conditionsallow primary alcoholic TBS ethers to be desilylated chemoselectively in the presence of phenolicTBS ethers, secondary and tertiary alcolholic TBS ethers, and the extensively used TBDPS-,acetyl-, benzyloxycarbonyl-, p-toluenesulfonyl- and benzyl protective groups.

关键词： tert-Butyldimethylsilyl (TBS) ethers deprotection tin dichloride

A Facile Synthesis of Spin Labeled 4′-Epi-N-Trifuoroactyldaunomycin Derivatives

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Chinese Chemical Letters 2001年第8期12卷 665-666页

作者： Xu Feng LIN, Cheng MA*, yan guang wang Department of Chemistry, Zhejiang University, Hangzhou 310027 Department of Chemistry Zhejiang University

The spin labeled 4(-Epi-N-trifuoroacetyldaunomycin derivatives 6-7 were conveniently synthesized from daunomycin in middle yield. The key steps were the protection of compd. 5 at 9-position and nucleophilic displaceme... 详细信息

关键词： Spin labeled daunomycin antitumor synthesis.

The Synthesis of 1-Aryl-5-Fluorouracil

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Chinese Chemical Letters 2000年第10期11卷 865-866页

作者： Jin Zong YOU Shao Yuan CHEN Omar ISHRUD yan guang wang Yao Zu CHEN Department of Chemistry Zhejiang UniversityHangzhou 310027 National Laboratory of Applied Organic Chemistry Lanzhou UniversityLanzhou 730000

A series of new type substituted 5-fluorouracil derivatives, 1-aryl-5-fluorouracil (4a-4f), were synthesized via diaryliodonium salts and the structure of the title compound was finally confirmed by IR, UV. H-1-NMR. M... 详细信息

关键词： synthesis 1-aryl-5-fluorouracil

Microwave-assisted Regioselective 1-O-Deacylation of Peracylated Glycopyranoses on Alumina

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Chinese Chemical Letters 2003年第9期14卷 904-906页

作者： Jia Qiang DONG, Shu Jia ZHANG, yan guang wang Department of Chemistry, Zhejiang University, Hangzhou 310027 Department of Chemistry Zhejiang University Hangzhou 310027

A facile, rapid and regioselective method for the 1-O-deacylation of peracylated glycopyranoses is described which occurs under mild conditions by absorption onto alumina using microwave irradiation.

关键词： Deacylation sugars regioselectivity microwave irradiation.

A Novel Method for Forecasting Freak Wave Occurrence in A Short Crested Coastal Sea

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China Ocean Engineering 2024年第1期38卷 104-116页

作者： wang Ying-guang State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240China School of Ocean and Civil Engineering Shanghai Jiao Tong UniversityShanghai 200240China

In order to forecast the distribution of crest amplitudes and the occurrence of freak waves in a short crested coastal sea,a novel transformed linear simulation method is initially proposed in this paper.A Hermite transformation model expressed as a monotonic cubic polynomial serves as the foundation for the novel simulation *** wave crest amplitude exceedance probabilities of two sea states-one with a directional wave spectrum based on the measured wave elevation data at the Yura coast and the other with a typical directional JONSWAP wave spectrum-have been predicted using the novel simulation method that has been *** likelihood that a particular critical wave crest amplitude will be exceeded is directly correlated with the probability that freak waves will *** is shown that the novel simulation approach suggested can provide predictions that are more precise than those obtained from the Rayleigh crest amplitude distribution model,the Jahns and Wheeler crest amplitude distribution model,or the conventional linear simulation *** study also demonstrated that the nonlinear simulation method is less effective than the novel simulation method in terms of efficiency.

关键词： wave crest amplitude freak waves short crested sea transformed linear simulation

Ti_(3)C_(2)T_(x)/SnO_(2)P–N heterostructure construction boosts room-temperature detecting formaldehyde

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Rare Metals 2024年第1期43卷 267-279页

作者： Yue Zhang Ming-Yue wang Xiao-guang San yan-Bai Shen Guo-Sheng wang Lei Zhang Dan Meng College of Chemical Engineering Shenyang University of Chemical TechnologyShenyang 110142China Institute for Superconducting and Electronic Materials(ISEM) Australian Institute for Innovative Materials(AIIM)University ofWollongongWollongongNSW2500Australia College of Resources and Civil Engineering Northeastern UniversityShenyang 110819China

Formaldehyde is a common atmospheric pollutant produced in industrial production and daily ***,the traditional semiconductor formaldehyde gas sensor cannot work at room temperature,which limits its practical ***,developing high-performance gas sensors for rapidly and accurately detecting formaldehyde at room temperature is an important *** this study,Ti_(3)C_(2)Tx/SnO_(2)heterostructures were constructed,which could selectively detect formaldehyde at room temperature with a response value of 29.16%(10×10^(-6)).In addition,the sensor shows a remarkable theoretical detection limit of 5.09×10^(-9)and good longterm *** functional theory(DFT)simulations reveal that SnO_(2)nano spheres provide the majority of adsorption sites that strongly interact with ***,Ti_(3)C_(2)T_(x)acting as a conductive layer facilitates the transfer of charge carriers so that they show a sensing response to formaldehyde at room ***,the formation of p-n heterostructures between SnO_(2)and Ti_(3)C_(2)T_(x)boosts the Schottky barrier at the interface,which is the critical factor in enhancing the sensing properties by turning the Schottky barrier upon introducing formaldehyde *** perspective is expected to provide instructive guidance for utilizing MXene/metal oxide nanocomposites to improve the gas sensing performance at room temperature.

关键词： Ti_(3)C_(2)T_(x)/SnO_(2)nanocomposites p-n heterostructures Formaldehyde sensing Room temperature DFT calculations

Metasurface-assisted low-frequency performance enhancement of ultra-broadband honeycomb absorber based on carbon nanotubes

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Nano Research 2024年第9期17卷 8542-8551页

作者： Cai-Liang wang Shuang Bai Pei-yan Zhao Tao Zhou Hui-Ya wang Jun-Peng wang Luo-Xin wang guang-Sheng wang School of Chemistry Beihang UniversityBeijing 100191China Aerospace Science and Industry Corporation of Wuhan Magnetoelectricity Co. Ltd.Wuhan 430070China College of Materials Science and Engineering Key Laboratory for New Textile Materials and Applications of Hubei ProvinceWuhan Textile UniversityWuhan 430200China School of Chemistry and Chemical Engineering Lingnan Normal UniversityZhanjiang 524048China School of Materials Science and Engineering Zhejiang Sci-Tech UniversityHangzhou 310018China

Here,we present a unique method to enhance the low-frequency absorption performance of a honeycomb absorber by integrating a *** geometrical dimensions of the proposed metasurface have been numerically *** introduction of the metasurface allows exploitation of its robust resonance and superior impedance matching in low-frequency bands,thereby improving microwave absorption *** incorporation of the metasurface does not impact the wave transmission performance of the honeycomb core absorber at high-frequency band,thus preserving its high-frequency *** broadens the absorption range,leading to an expanded *** results reveal that the composite absorber(CA)exhibits strong absorption performance with an incident angle stability up to 45°for both transverse electric(TE)and transverse magnetic(TM)*** absorption mechanism of the CA has been investigated by using an equivalent circuit model and electromagnetic field analysis.A prototype was designed,fabricated,and tested to validate the proposed *** simulation and measurement results demonstrate that the prototype can achieve an average absorption rate exceeding 90%across a 1.0-18.0 GHz *** study introduces an innovative technique for creating microwave absorbers for low-frequency wideband applications.

关键词： low frequency metasurface radar absorption impedance matching

Porous Ti_(3)C_(2)T_(x) MXene nanosheets sandwiched between polyimide fiber mats for electromagnetic interference shielding

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Nano Research 2024年第3期17卷 2070-2078页

作者： Wenhao Liang Juntao Wu Shan Zhang Pei-yan Zhao Yi Cong Yongqiang Guo guang-Sheng wang Key Laboratory of Bioinspired Smart Interfacial Science and Technology of Ministry of Education School of ChemistryBeihang UniversityBeijing 100191China

With the rapid development of wireless communication technology and electronic devices,the issue of electromagnetic interference(EMI)is becoming increasingly *** a new and flexible electromagnetic interference shielding material has become a challenging ***,a sandwich-structured EMI shielding composite film was prepared using electrospinning and vacuum filtration *** this process,a porous MXene was synthesized through a reaction with cobalt acetate and served as the intermediate layer in the composite film to shield electromagnetic *** electrospun polyimide(PI)fibers were used as the top and bottom layers of the composite film,which can protect the porous MXene from *** lightweight and flexible composite film integrates electromagnetic interference shielding and thermal insulation capabilities,showing excellent comprehensive *** composite film achieves an EMI shielding effectiveness of 48.8 dB in X-band(8.2–12.4 GHz),and absolute shielding effectiveness of the composite film reached a satisfying 4142.43(dB·cm^(2))/*** to the design of a multi-layer porous structure,the density of the composite film is 0.65 g/***,the thermal conductivity of the film is 0.042 W/(m·K)due to the clamping of electrospun PI fibers,showing excellent thermal insulation ***,the composite film exhibits excellent high and low-temperature *** summary,this work provides a feasible strategy for preparing a lightweight polymer-based EMI shielding film.

关键词： porous MXene polyimide electromagnetic interference shielding thermal insulation