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| 1 | A Novel Method for Synthesizing p-Benzoquinone by Direct Catalytic Oxidation of Benzene with Hydrogen Peroxide over Copper-Doped TS-1显示文摘E xisting methods for synthesizing p -benzoquinone have drawbacks with respect to environmental protection, production scale, or industrial value. Therefore, it is imperative that a simple and environmentally friendly alternative be developed. The approach that involves preparing p -benzoquinone by the catalytic oxidation of benzene with hydrogen peroxide (H 2 O 2 ) over copper-modi ed titanium silicalite-1 (Cu/TS-1) has a certain superiority due to its green synthesis and mild reaction condi- tions. In this study, Cu/TS-1 catalyst was prepared by the wet impregnation of TS-1 with an aqueous solution of Cu(NO 3 ) 2 and then characterized by X-ray di raction, Fourier transform infrared spectroscopy, di use re ectance UV Vis spectros- copy, scanning electron microscopy, inductively coupled plasma mass spectrometry, X-ray uorescence, and analysis of the N 2 adsorption desorption isotherms. The results reveal that Cu species exist mainly in the form of amorphous CuO that is well dispersed on the surface of catalysts, with no major change in the molecular sieve framework. After optimizing the reaction conditions, a desirable p -benzoquinone selectivity (88.4%) and benzene conversion (18.3%) were obtained when the doping of Cu in Cu/TS-1 is 1.95 wt%. In addition, Cu/TS-1 can be conveniently regenerated, showing a slight decrease in catalytic capability after initial use, which then stabilizes in subsequent circulations. The satisfactory stability and low cost of synthesizing Cu/TS-1 give this method considerable potential for further industrialization. | Chenxiaodong Li Qingjun Zhang Aiwu Zeng | 2019 | Transactions of Tianjin University2019，25，5： | 1 |
| 2 | Kinetics and Mechanism Modeling of Liquid-Phase Toluene Oxidation to Benzaldehyde Catalyzed by Mn–Mo Oxide显示文摘In this study, liquid-phase aerobic oxidation of toluene catalyzed by Mn–Mo oxide was conducted in a 1.0 L batch reactor. The macroscopic kinetics of toluene consumption and benzaldehyde generation at 413–443 K were obtained from a combination of experimental observation and hypothetical models. The results clearly showed that both the oxidation rate of toluene and generation rate of the aromatic product were proportional to the concentration of the substrate, the partial pressure of oxygen and the surface area of the catalyst. The energy barrier of toluene oxidation to benzyl alcohol was the highest(≈ 81 kJ mol^(-1)), while that of benzyl alcohol oxidation to benzaldehyde was the lowest(≈ 57 kJ mol^(-1)). Moreover, the activation energy of further oxidation of benzaldehyde in an acetic acid solvent was only slightly lower(≈ 1.9 kJ mol^(-1)) than that of toluene oxidation. Significantly, the transformation of benzyl alcohol indeed contributed to the generation of benzaldehyde and this step conformed to a first-order parallel-consecutive model. Increased reaction temperature and residence time favored the transformation of benzyl alcohol to benzaldehyde. In addition, doping with molybdenum at Mn/Mo = 3/1 enhanced the catalytic performance of the heterogeneous catalyst and was attributed to the presence of a synergetic effect between different metal cations. Regarding the microscopic kinetics, the LH-OS-ND mechanism(Langmuir–Hinshelwood adsorption of reagents on the same type of active sites and non-dissociative adsorption of oxygen) was verified as responsible for the heterogeneous oxidation of toluene. Oxygen and benzaldehyde were weakly adsorbed(Δ H_(ads,Oxy) ≈^(-1)5 kJ mol^(-1), Δ H _(ads)0,Bald) ≈-30 kJ mol^(-1)), but showed strong mobility(Δ S_(ads,Oxy) ≈-22 J mol^(-1) K^(-1)), Δ S_(ads,Bald) ≈-39 J mol^(-1) K^(-1)). The fundamental intrinsic rates were deduced based on the LH-OS-ND mechanism and showed great consistency with the macroscopic results. | Wang Li Qingjun Zhang Aiwu Zeng | 2019 | Transactions of Tianjin University2019，25，1： | 1 |
| 3 | Single-dose AAV-based vaccine induces a high level of neutralizing antibodies against SARS-CoV-2 in rhesus macaques显示文摘Dear Editor,Coronavirus disease 2019(COVID-19)is a highly infectious respiratory disease that continues to pose a serious global public health emergency.The disease shows a high infection rate,long incubation period,and rapidly emerging variants,which have led to its rapid spread worldwide(Krammer 2020).Many vaccines have been developed for the control of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),the virus responsible for COVID-19,including vaccines based on messenger RNA(mRNA)(Polack et al.2020),viral vectors(Zhu et al.2020),recombinant proteins(Yang et al.2020),and inactivated SARS-CoV-2(Zhang et al.2021). | Dali Tong Mei Zhang Yunru Yang Han Xia Haiyang Tong Huajun Zhang Weihong Zeng Muziying Liu Yan Wu Huan Ma Xue Hu Weiyong Liu Yuan Cai Yanfeng Yao Yichuan Yao Kunpeng Liu Shifang Shan Yajuan Li Ge Gao Weiwei Guo Yun Peng Shaohong Chen Juhong Rao Jiaxuan Zhao Juan Min Qingjun Zhu Yanmin Zheng Lianxin Liu Chao Shan Kai Zhong Zilong Qiu Tengchuan Jin Sandra Chiu Zhiming Yuan Tian Xue | 2023 | Protein & Cell2023，14，1： | 0 |
| 4 | Raltitrexed as a synergistic hyperthermia chemotherapy drug screened in patient-derived colorectal cancer organoids显示文摘Objective:Organoids have recently been used as in vitro models to screen chemotherapy drugs in combination with hyperthermia treatment in colorectal cancer.Our research aimed to establish a library of patient-derived colorectal cancer organoids to evaluate synergism between chemotherapy drugs and hyperthermia;validate an index of the hyperthermia chemotherapy sensitization enhancement ratio(HCSER)to identify the chemotherapeutics most enhanced by hyperthermia;and recommend chemotherapy drugs for hyperthermic intraperitoneal treatment.Methods:Organoids were grown from cells extracted from colorectal cancer patient samples or colorectal cancer cell lines.Cells from both sources were encapsulated in 3 D Matrigel droplets,which were formulated in microfluidics and phase-transferred into identical cell-laden Matrigel microspheres.The microspheres were seeded in 96-well plates,with each well containing a single microsphere that developed into an organoid after 7 days.The organoids were used to evaluate the efficacy of chemotherapy drugs at both 37℃ as a control and 43℃ for 90 min to examine hyperthermia synergism.Cell viability was counted with 10%CCK8.Results:We successfully established a library of colorectal cancer organoids from 22 patient parental tumors.We examined the hyperthermia synergism of 7 commonly used hyperthermic intraperitoneal chemotherapy drugs.In 11 of the 22 patient organoids,raltitrexed had significant hyperthermia synergism,which was indexed as the highest HCSER score within each patient group.Conclusions:Our results primarily demonstrated the use of patient-derived colorectal cancer organoids as in vitro models to evaluate hyperthermia synergistic chemotherapeutics.We found that hyperthermia enhanced the effect of raltitrexed the most among the common anti-colorectal cancer drugs. | Lisi Zeng Quanxing Liao Haoran Zhao Shengwei Jiang Xianzi Yang Hongsheng Tang Qingjun He Xiansheng Yang Shuxian Fang Jinfu He Weiwen Cui Laiqiang Huang Shaohua Ma Shuzhong Cui | 2021 | Cancer Biology & Medicine2021，18，3： | 0 |
| 5 | Electrocoagulation coupled with electrooxidation for the simultaneous treatment of multiple pollutants in contaminated sediments显示文摘In situ and simultaneous remediation of a variety of pollutants in sediments remains a challenge.In this study,we report that the combination of electrocoagulation(EC)and electrooxidation(EO)is efficient in the immobilization of phosphorus and heavymetals and in the oxidation of ammonium and toxic organicmatter.The integratedmixed metal oxide(MMO)/Fe anode system allowed the facile removal of ammonium and phosphorus in the overlying water(99% of 10 mg/L NH_(4)^(+)-N and 95% of 10 mg/L P disappeared in 15 and 30 min,respectively).Compared with the controls of the single Fe anode and single MMO anode systems,the dual MMO/Fe anode system significantly improved the removal of phenanthrene and promoted the transition of Pb and Cu from the mobile species to the immobile species.The concentrations of Pb and Cu in the toxicity characteristic leaching procedure extracts were reduced by 99%and 97% after an 8 hr operation.Further tests with four real polluted samples indicated that substantial proportions of acid-soluble fraction Pb and Cu were reduced(30%-31% for Pb and 16%–23% for Cu),and the amounts of total organic carbon and NH_(4)^(+)-N decreased by 56%–71% and 32%–63%,respectively.It was proposed that the in situ electrogenerated Fe(II)at the Fe anode and the active oxygen/chlorine species at the MMO anode are conducive to outstanding performance in the co-treatment of multiple pollutants.The results suggest that the EC/EO method is a powerful technology for the in situ remediation of sediments contaminated with different pollutants. | Qingjun Zeng Yifan Zhang Pingshan Chen Yuting He Congli Yi Chunhua Feng | 2023 | Journal of Environmental Sciences2023，，2： | 0 |
| 6 | Box-Behnken experimental design for optimizing process parameters in carbonate-promoted direct thiophene carboxylation reaction with carbon dioxide显示文摘A feasible synthesis route is developed for achieving the direct carboxylation of thiophene and CO_(2) in a relatively mild solvent-free carboxylate-assisted carbonate(semi)molten state.The effects of reaction factors on the carboxylate yield are investigated in the preliminary screening experiments,and the phase behavior analysis of the reaction medium is detected through the thermal characterization analysis of insitu high temperature X-ray diffraction measurement(in-situ XRD).The application of response surface methodology(RSM)based on the Box-Behnken design(BBD)is conducted to investigate the effect of the reaction parameters,such as reaction temperatu re,carbonate proportion,CO_(2) pressure and thiophene amount,on the product yield.The regressed second-order polynomial model equation well correlates all the independent variables.The analysis of variance(ANOVA)results reveal that the quadratic effect of reaction temperature is the most effective parameter in this carboxylation reaction owing to it’s the highest contribution to the sum of square(30.18%).The optimum reaction conditions for maximum product yield are the reaction temperature of 287℃,carbonate proportion of 32.20%,CO_(2) pressure of 1.0MPa and thiophene amount of 9.35 mmol.Operating under these selected experimental conditions,a high product yield(50.98%)can be achieved. | Qingjun Zhang Youguang Ma Xigang Yuan Aiwu Zeng | 2022 | Chinese Journal of Chemical Engineering2022，，10： | 0 |
| 7 | Direct carboxylation of thiophene with CO_(2) in the solvent-free carboxylate-carbonate molten medium:Experimental and mechanistic insights显示文摘A feasible synthesis route is devised for realizing direct carboxylation of thiophene and CO_(2) in a relatively mild solvent-free carboxylate-assisted carbonate(semi)molten medium.The effects of reaction factors on product yield are investigated,and the phase behavior analysis of the reaction medium is detected through the thermal characterization techniques.Product yield varies with the alternative carboxylate co-salts,which is attributed to the difference in deprotonation capacity caused by the base effect within the system.Besides,the detailed mechanism of this carbonate-promoted carboxylation reaction is studied,including two consecutive steps of the formation of carbanion through breaking the C-H bond(s)via the carbonate and the nucleophile attacking the weak electrophile CO_(2) to form C-C bond(s).The activation energy barrier in C-H activation step is higher than the following CO_(2) insertion step whether for the formation of the mono-and/or di-carboxylate,which is in good agreement with that of kinetic isotope effect(KIE)experiments,indicating that the C-H deprotonation is slow and the forming presumed carbanion reacts rapidly with CO_(2).Both the activation energy barriers in deprotonation steps are the minimal for the cesium cluster system since there have the weak the cesium Cs-heteroatom S(thiophene)and Cs-the broken proton interactions compared to the K2CO3 system,which is likely to enhance the acidity of C-H bond,lowering the C-H activation barrier.Besides,these mechanistic insights are further assessed by investigating base and C-H substrate effects via replacing Cs2CO3 with K2CO3 and furoate(la)with thiophene monocarboxylate(1b)or benzoate(1c). | Qingjun Zhang Pengyuan Shi Xigang Yuan Youguang Ma Aiwu Zeng | 2022 | Chinese Journal of Chemical Engineering2022，，10： | 0 |
| 8 | Separation of n-heptane/isobutanol via eco-efficient vapor recompression-assisted distillation:process optimization and control strategy显示文摘In this study,vapor recompression and heat integration assisted distillation arrangements with either the low or high pressure in the reflux drum are proposed to reduce and/or eliminate the application of the costly refrigerant for the separation of n-heptane and isobutanol mixture.The high-pressure arrangement with vapor recompression and heat integration is the most attractive among these four intensified configurations since it can reduce total annual cost by 18.10%,CO_(2) emissions by 75.01%based on natural gas(78.78%based on heavy oil fuel),and second-law efficiency by 61.20%compared to a conventional refrigerated distillation system.Furthermore,exergy destruction in each component is calculated for the heat integration configurations and is shown in pie diagrams.The results demonstrate that the high-pressure configuration presents unique advantages in terms of thermodynamic efficiency compared to the low-pressure case.In addition,dynamic control investigation is performed for the economically efficient arrangement and good product compositions are well controlled through a dual-point temperature control strategy with almost negligible product offsets and quick process responses when addressing 20%step changes in production rate and feed composition.Note that there are no composition measurement loops in our developed control schemes. | Wei Hou Qingjun Zhang Aiwu Zeng | 2021 | Frontiers of Chemical Science and Engineering2021，15，5： | 0 |
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