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Sodium Bisulfite： An Efficient Catalyst for Ether Formation via Dehydration of Aromatic/Aliphatic Alcohol

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Chinese Journal of Chemistry 2011年第6期29卷 1180-1184页

作者： Wang, Hui Zhu, Xingfei lu, Yangning Li, Yue gao, xiang Chemistry Department Fudan University Shanghai 200433 China School of Life Sciences Fudan University Shanghai 200433 China

Straightforward etherification of benzyl alcohols （1） via intermolecular dehydration can be efficiently catalyzed by sodium bisulfite under solvent-free conditions. In the presence of 0.3 mol% or 0.6 mol% amount of sodium bisulfite, symmetric and unsymmetric ethers are prepared from the corresponding alcohols in high yields （up to 95%）. Etherification of benzhydryl alcohols is also discussed.

关键词： sodium bisulfite etherification dehydration aromatic alcohol aliphatic alcohol

3D core-shell nanofibers framework and functional ceramic nanoparticles synergistically reinforced composite polymer electrolytes for high-performance all-solid-state lithium metal battery

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Chinese Chemical Letters 2024年第8期35卷 425-432页

作者： Hengying xiang Nanping Deng lu.gao Wen Yu Bowen Cheng Weimin Kang State Key Laboratory of Separation Membranes and Membrane Processes Tiangong UniversityTianjin 300387China School of Textile Science and Engineering Tiangong UniversityTianjin 300387China

Satisfactory ionic conductivity,excellent mechanical stability,and high-temperature resistance are the prerequisites for the safe application of solid polymer electrolytes(SPEs)in all-solid-state lithium metal batteries(ASSLMBs).In this study,a novel poly(m-phenylene isophthalamide)(PMIA)-core/poly(ethylene oxide)(PEO)-shell nanofiber membrane and the functional Li_(6.4)La_(3)Zr_(1.4)Ta_(0.6)O_(12)(LLZTO)ceramic nanopar-ticle are simultaneously introduced into the PEO-based SPEs to prepare composite polymer electrolytes(CPEs).The core PMIA layer of composite nanofibers can greatly improve the mechanical strength and thermal stability of the CPEs,while the shell PEO layer can provide the 3D continuous transport channels for lithium *** addition,the introduction of functional LLZTO nanoparticle not only reduces the crys-tallinity of PEO,but also promotes the dissociation of lithium salts and releases more Li^(+)ions through its interaction with the Lewis acid-base of anions,thereby overall improving the transport of lithium ***,the optimized CPEs present high ionic conductivity of 1.38×10^(−4)S/cm at 30℃,signifi-cantly improved mechanical strength(8.5 MPa),remarkable thermal stability(without obvious shrinkage at 150℃),and conspicuous Li dendrites blocking ability(>1800 h).The CPEs also both have good com-patibility and cyclic stability with LiFePO_(4)(>2000 cycles)and high-voltage LiNi_(0.8)Mn_(0.1)Co_(0.1)O_(2)(NMC811)(>500 cycles)*** addition,even at low temperature(40℃),the assembled LiFePO4/CPEs/Li bat-tery still can cycle *** novel design can provide an effective way to exploit high-performance solid-state electrolytes.

关键词： Composite polymer electrolytes Core-shell structured nanofiber Li_(6.4)La_(3)Zr_(1.4)Ta_(0.6)O_(12)ceramic nanoparticle All-solid-state lithium metal batteries Outstanding thermal stability and electrochemical performance

Degradation of benzothiophene in diesel oil by LaZnAl layered double hydroxide: photocatalytic performance and mechanism

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Petroleum Science 2019年第1期16卷 173-179页

作者： Li-Guo gao Huan-xiang Li Xiao-Li Song Wan-lu Li xiang-Rong Ma School of Chemistry and Chemical Engineering Yulin University Department of Chemistry Tsinghua University

A new type of photocatalytic La^(3+)–Zn^(2+)–Al^(3+)–MoO_4^(2-) layered double hydroxide(LDH) material(molar ratio, La/Zn/Al = 1:7:2) was prepared by a complexing agent-assisted homogeneous precipitation technique. The structure of the prepared LDH material was systematically studied. Under UV irradiation, the desulfurization efficiency of the LDH material was 87% in 2 h. For La^(3+)–Zn^(2+)–Al^(3+)–MoO_4^(2-) LDH material, the introduction of MoO_4^(2-) increased the interlayer space for promoting the adsorption of benzothiophene(BT), and MoO_4^(2-) might provide active sites for the oxidation of BT, resulting in the high desulfurization efficiency.

关键词： LDH Homogeneous precipitation Photocatalytic activities Catalytic oxidation mechanism

Efficient practical codebook-precoding MIMO scheme based on signal space diversity

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Journal of Systems Engineering and Electronics 2016年第1期27卷 1-9页

作者： Zhanji Wu xiang gao School of Information and Communication Engineering Beijing University of Posts and Telecommunications

A novel practical codebook-precoding multiple-input multiple-output（MIMO） system based on signal space diversity（SSD） with the minimum mean squared error（MMSE）receiver is *** scheme utilizes rotation modulation and space-time-frequency component interleaving.A novel precoding matrix selection criterion to maximize the average signal to interference plus noise ratio（SINR） is also put forward for the proposed scheme,which has a larger average mutual information（AMI）.Based on the AMI- maximization criterion,the optimal rotation angles for the proposed system are also *** new scheme can make full use of space-time-frequency diversity and signal space diversity,and exhibit high spectral efficiency and high reliability in fading *** results show that the proposed scheme greatly outperforms the conventional bit- interleaved coded modulation（BICM） MIMO-orthogonal frequency division multiplexing（OFDM） scheme without SSD,which is up to4.5 dB signal-to-noise ratio（SNR） gain.

关键词： signal space diversity(SSD) average mutual information(AMI) Turbo code multiple-input multiple-output(MIMO) minimum mean squared error(MMSE).

Improved MIMO-OFDM scheme for the next generation WLAN

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Journal of Systems Engineering and Electronics 2013年第1期24卷 52-59页

作者： Zhanji Wu xiang gao School of Information and Communication Engineering Beijing University of Posts and Telecommunications

The research and application of wireless local area networks （WLAN） technology are in a stage of rapid development. It has been one of research focuses of the wireless communications field. Through the use of enhanced single-user （SU）/multi-user （MU） multiple input multiple output （MIMO）-orthogonal frequency division multiplexing （OFDM） technology, the next generation WLAN IEEE 802.1 lac dramatically increases the throughput. An improved MIMO-OFDM scheme based on modulation diversity is proposed for the next generation WLAN. It uses two-dimensional modulation diversity to the current IEEE 802.11ac transmission scheme. Through the space-time-frequency component inter- leaver and the rotational modulation, the proposed scheme ex- hibits high spectral efficiency and low error rate in fading channels. The simulation results show that the proposed scheme significantly outperforms the SU/MU MIMO-OFDM scheme in the current IEEE 802.11 ac standard, which is up to 5 dB.

关键词： wireless local area networks (WLAN) I EEE 802.1 lac modulation diversity multiple input multiple output (MIMO) orthog- onal frequency division multiplexing (OFDM).

The Role of Mold Temperature on Morphology and Mechanical Properties of PE Pipe Produced by Rotational Shear

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Chinese Journal of Polymer Science 2020年第6期38卷 653-664页

作者： Zu-Chen du Hao Yang Xie-Huai luo Ze-xiang Xie Qiang Fu Xue-Qin gao College of Polymer Science and Engineering Sichuan UniversityChengdu 610065China

The role of mold temperature on the morphology and properties of rotational shearing polyethylene(PE)pipes was studied via a self-.developed rotational shear system(RSS).The result indicated that when the mold temperature was 150℃,the hoop tensile strength and Vicat softening temperature were enhanced rapidly,which were 383.6%and 137.9%higher than those of the conventional PE pipes,*** and crystal structure studies by SEM and DSC revealed that once the rotational shear was applied,the shish-kebab structure began to *** the increase of the mold temperature,due to the relaxation of most of the oriented molecular chains,the preservation of shish-kebab structure became *** the mold temperature was 190℃,only the inner layer of the pipes,where the cooling rate was the largest,could preserve the shish-kebab *** to WAXD,there was less shish structure,and the growth of kebab was distorted in the inner layer of the pipes at 210℃.The result of SAXS suggested that the length of shish changed most within the temperature range from 170℃to 190。*** results of DSC and WAXD showed less change in crystallinity and degree of orientation between the two *** can be concluded that the reduction of shish length leads to a decrease in mechanical properties and heat-resistance.

关键词： Shish-kebab Rotational shear Mold temperature PE pipe

A new method to prepare calcium oxalate films for marble protection

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Science China(Technological Sciences) 2023年第8期66卷 2237-2245页

作者： HE lu JIANG YiJie MA WenTing LIU Yan YANG FuWei lu RuiCong WANG lu ZHANG Kun CHEN XinNan gao xiang China-Central Asia“the Belt and Road”Joint Laboratory on Human and Environment Research Key Laboratory of Cultural Heritage Research and ConservationSchool of Culture HeritageNorthwest UniversityXi’an 710127China College of Chemistry and Materials Science Northwest UniversityXi’an 710069China

Artificial calcium oxalate films have been applied to protect sculptures,monuments,and buildings made of marble due to their potential protective ***,artificially prepared calcium oxalate films are usually loose,and easy to peel off in contrast to the natural *** this paper,a new method was developed for the preparation of a compact and cohesive calcium oxalate film,using ethylene glycol as an *** morphology,elemental composition,structure,and crystal phase of the film were analyzed by SEM,EDX,IR,and XRD,and the protective effects were investigated by acid resistance test,while its adhesion to the underlying marble by the Scotch tape *** porosity,water absorption,and color of treated marble were also *** results showed that a calcium oxalate film with a compact structure,good adhesion,and a protective effect against acid rain can be successfully obtained by including ethylene glycol as an *** the new preparation method,a better bond between the stone and the film is obtained which contributes to solving the spalling problem of the artificial calcium oxalate films.

关键词： marble calcium oxalate film ethylene glycol protection

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Synthesis and Properties of Novel luminescent Compounds Containing Triphenylamine and Bipyridine Units

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Chemical Research in Chinese Universities 2012年第2期28卷 313-318页

作者： lu Hai-jun LI xiang-gao WANG Shi-rong gao Wen-zheng WANG Sha-sha School of Chemical Engineering and Technology Tianjin UniversityTianjin 300072P.R.China College of Chemical and Pharmaceutical Engineering Hebei University of Science and TechnologyShijiazhuang 050018P.R.China

Blue luminescent compounds T1―T4 containing triphenylamine donors,bipyridine acceptors and olefinic linkers were synthesized and characterized by 1 H NMR,13 C NMR and high resolution mass spectrometry（HRMS）.Four compounds T1―T4 exhibit excellent solubility in common solvents and good film forming *** chemical calculations show that compounds T1―T4 have asymmetric linear structures and the proper highest occupied molecular orbital（HOMO） *** UV-Vis absorption and fluorescence emission spectra of the four compounds in dilute chloroform solutions and on the solid films were *** reveals that compounds T1―T4 exhibit similar spectral behavior,suggesting that these compounds can form amorphous state in solid *** calculated absorption and emission spectra of compounds T1―T4 are in good agreement with experimentally determined *** T1―T4 have absolute fluorescence quantum yield above 17% in dilute chloroform *** compounds possess high glass-transition temperature（T g） exceeding 97 ℃ and the maximum T g is 155.28 ℃ for compound *** voltammetry measurements show that these compounds have proper HOMO levels in a range of-5.01―-5.13 eV for hole *** properties of compounds T1―T4 indicate that these compounds are candidates for the application in organic light-emitting devices（OLEDs） as hole-transporting materials（HTMs）.

关键词： luminescent compound Triphenylamine Bipyridine Hole-transporting material

Time Series and Spatial Epidemiological Analysis of the Prevalence of Iodine Deficiency Disorders in China

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Biomedical and Environmental Sciences 2022年第8期35卷 735-745页

作者： FAN Li Jun gao Yun Yan MENG Fan Gang LIU Chang LIU Lan Chun du Yang LIU Li xiang LI Ming SU Xiao Hui LIU shou Jun LIU Peng Institute of lodine DeficiencyDisorders Center for Endemic Disease ControlChinese Center forDisease Control and PreventionHarbin Medical UniversityHarbin 150081HeilongjiangChina National Health Commission&Education Bureau of Heilongjiang Province Key laboratory of Etiology and EpidemiologyHarbin Medical UniversityHarbin 150081HeilongjiangChina

Objective To recognize the spatial and temporal characteristics of iodine deficiency disorders(IDD),China national IDD surveillance data for the years of 1995–2018 were *** Time series analysis was used to describe and predict the IDD related indicators,and spatial analysis was used to analyze the spatial distribution of salt iodine *** In China,the median urinary iodine concentration increased in 1995–1997,then decreased to adequate levels,and are expected to remain appropriate in 2019–*** goiter rate continually decreased and is expected to be maintained at a low *** 2002,the coverage rates of iodized salt and the consumption rates of qualified iodized salt(the percentage of qualified iodized salt in all tested salt) increased and began to decline in 2012;they are expected to continue to *** epidemiological analysis indicated a positive spatial correlation in 2016–2018 and revealed feature regarding the spatial distribution of salt related indicators in coastal areas and areas near iodine-excess *** Iodine nutrition in China showed gradual ***,a recent decline has been observed in some areas following changes in the iodized salt supply in *** the future,more regulations regarding salt management should be issued to strengthen IDD control and prevention measures,and avoid the recurrence of IDD.

关键词： Salt iodine lodine deficiency disorders Time series analysis Space epidemiology Reform for the salt industry system