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Zn_(x)Zr/HZSM-5 as efficient catalysts for alkylation of benzene with carbon dioxide

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Frontiers of Chemical Science and Engineering 2023年第4期17卷 404-414页

作者： Junjun Cheng Yitao Zhao Guohao Xu Peng Zhang Xuedong Zhu Fan Yang Engineering Research Center of Large-Scale Reactor Engineering and Technology Ministry of EducationEast China University of Science&TechnologyShanghai 200237China

Alkylation of benzene with carbon dioxide and hydrogen to produce toluene and xylene could increase the added-value of surplus benzene as well as relieve environmental problems like green-house effect.In this work,the alkylation benzene with carbon dioxide and hydrogen reaction was proceeded by using the mixture of zinc-zirconium oxide and HZSM-5 as bifunctional catalyst.The equivalent of Zn/Zr=1 displays the best catalytic performance at 425℃ and 3.0 MPa,and benzene conversion reaches 42.9%with a selectivity of 90%towards toluene and xylene.Moreover,the carbon dioxide conversion achieves 23.3%and the carbon monoxide selectivity is lower than 35%,indicating that more than 50%carbon dioxide has been effectively incorporated into the target product,which is the best result as far as we know.Combined with characterizations,it indicated that the Zn and Zr formed a solid solution under specific conditions(Zn/Zr=1).The as-formed solid solution not only possesses a high surface area but also provides a large amount of oxygen vacancies.Additionally,the bifunctional catalyst has excellent stabilities that could keep operating without deactivation for at least 80 h.This work provides promising industrial applications for the upgrading of aromatics.

关键词： carbon dioxide alkylation of benzene solid solution catalyst bifunctional catalyst

Complete moment convergence for weighted sums of widely orthant-dependent random variables and its application in nonparametric regression models

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Frontiers of Mathematics in China 2022年第4期17卷 571-590页

作者： Lu cheng junjun LANG Yan SHEN Xuejun WANG School of Mathematical Sciences Anhui UniversityHefei230601China

We establish some results on the complete moment convergence for weighted sums of widely orthant-dependent(WOD)random variables,which improve and extend the corresponding results of Y.F.Wu,M.G.Zhai,and J.Y.Peng[J.Math.Inequal.,2019,13(1):251–260].As an application of the main results,we investigate the complete consistency for the estimator in a nonparametric regression model based on WOD errors and provide some simulations to verify our theoretical results.

关键词： Widely orthant-dependent random variables complete moment convergence nonparametric regression model

Establishment of drug-resistant HBV small-animal models by hydrodynamic injection

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Acta Pharmaceutica Sinica B 2014年第4期4卷 270-276页

作者： Junjun Cheng Yanxing Han Jian-Dong Jiang State Key Laboratory of Bioactive Substances and Function of Natural Medicine Institute of Materia MedicaChinese Academy of Medical SciencesBeijing 100050China

In antiviral therapy of hepatitis B virus(HBV)infection,drug resistance remains a huge obstacle to the long-term effectiveness of nucleoside/tide analogs(NAs).Primary resistance mutation(rtM204V)contributes to lamivudine(LAM)-resistance,and compensatory mutations(rtL180M and rtV173L)restore viral fitness and increase replication efficiency.The evaluation of new anti-viral agents against drug-resistant HBV is limited by the lack of available small-animal models.We established LAM-resistance HBV replication mice models based on clinical LAM-resistant HBV mutants.Double(rtM204VþrtL180M)or triple(rtM204VþrtL180MþrtV173L)lamivudine-resistant mutations were introduced into HBV expression vector,followed by hydrodynamic injection into tail vein of NOD/SCID mice.Viremia was detected on days 5,9,13 and 17 and liver HBV DNA was detected on day 17 after injection.The serum and liver HBV DNA levels in LAM-resistant model carrying triple mutations are the highest among the models.Two NAs,LAM and entecavir(ETV),were used to test the availability of the models.LAM and ETV inhibited viral replication on wild-type model.LAM was no longer effective on LAM-resistant models,but ETV retains a strong activity.Therefore,these models can be used to evaluate anti-viral agents against lamivudine-resistance,affording new opportunities to establish other drug-resistant HBV small-animal models.

关键词： Drug-resistance Animal models Hepatitis B virus Hydrodynamic injection

An Image Steganography Algorithm Based on Quantization Index Modulation Resisting Scaling Attacks and Statistical Detection

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Computers, Materials & Continua 2018年第7期56卷 151-167页

作者： Yue Zhang Dengpan Ye junjun Gan Zhenyu Li Qingfeng cheng State Key Laboratory of Mathematical Engineering and Advanced Computing Zhengzhou 450001China Computer School of Wuhan University Wuhan 430072China Department of Computer Science University of YorkYork YO105GHUK

In view of the fact that the current adaptive steganography algorithms are difficult to resist scaling attacks and that a method resisting scaling attack is only for the nearest neighbor interpolation method,this paper proposes an image steganography algorithm based on quantization index modulation resisting both scaling attacks and statistical detection.For the spatial image,this paper uses the watermarking algorithm based on quantization index modulation to extract the embedded domain.Then construct the embedding distortion function of the new embedded domain based on S-UNIWARD steganography,and use the minimum distortion coding to realize the embedding of the secret messages.Finally,according to the embedding modification amplitude of secret messages in the new embedded domain,the quantization index modulation algorithm is applied to realize the final embedding of secret messages in the original embedded domain.The experimental results show that the algorithm proposed is robust to the three common interpolation attacks including the nearest neighbor interpolation,the bilinear interpolation and the bicubic interpolation.And the average correct extraction rate of embedded messages increases from 50%to over 93% after 0.5 times-fold scaling attack using the bicubic interpolation method,compared with the classical steganography algorithm S-UNIWARD.Also the algorithm proposed has higher detection resistance than the original watermarking algorithm based on quantization index modulation.

关键词： Image steganography anti-scaling attack anti-statistical detection quantization index modulation

Integrating thermal energy storage and microwave absorption in phase change material-encapsulated core-sheath MoS_(2)@CNTs

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Journal of Energy Chemistry 2023年第9期84卷 41-49页

作者： Panpan Liu Yang Li Zhaodi Tang junjun Lv Piao cheng Xuemei Diao Yu Jiang Xiao Chen Ge Wang Institute of Advanced Materials Beijing Normal UniversityBeijing 100875China College of Nuclear Science and Technology Beijing Normal UniversityBeijing 100875China Beijing Advanced Innovation Center for Materials Genome Engineering Beijing Key Laboratory of Function Materials for Molecule&Structure ConstructionSchool of Materials Science and EngineeringUniversity of Science and Technology BeijingBeijing 100083China

Developing advanced nanocomposite integrating solar-driven thermal energy storage and thermal management functional microwave absorption can facilitate the cutting-edge application of phase change materials(PCMs).To conquer this goal,herein,two-dimensional MoS_(2) nanosheets are grown in situ on the surface of one-dimensional CNTs to prepare core-sheath MoS_(2)@CNTs for the encapsulation of paraffin wax(PW).Benefiting from the synergistic enhancement photothermal effect of MoS_(2) and CNTs,MoS_(2)@CNTs is capable of efficiently trapping photons and quickly transporting phonons,thus yielding a high solar-thermal energy conversion and storage efficiency of 94.97%.Meanwhile,PW/MoS_(2)@CNTs composite PCMs exhibit a high phase change enthalpy of 101.60 J/g and excellent lo ng-term thermal storage durability after undergoing multiple heating-cooling cycles.More attractively,PW/MoS_(2)@CNTs composite PCMs realize thermal management functional microwave absorption in heat-related electronic application scenarios,which is superior to the single microwave absorption of traditional materials.The minimum reflection loss(RL) for PW/MoS_(2)@CNTs is-28 dB at 12.91 GHz with a 2.0 mm thickness.This functional integration design provides some insightful references on developing advanced microwave absorbing composite PCMs,holding great potential towards high-efficiency solar energy utilization and thermally managed microwave absorption fields.

关键词： Phase change materials Core-sheath MoS_(2)@CNTs Solar-thermal energy conversion Thermal energy storage Microwave absorption

Oat bran and wheat bran impact net energy by shaping microbial communities and fermentation products in pigs fed diets with or without xylanase

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Journal of Animal Science and Biotechnology 2021年第1期12卷 386-401页

作者： Zhiqian Lyu Li Wang Jinrong Wang Zhenyu Wang Shuai Zhang junjun Wang Jinlong cheng Changhua Lai State Key Laboratory of Animal Nutrition College of Animal Science and TechnologyChina Agricultural UniversityNo.2 Yuanmingyuan West RoadBeijing 100193China INRA-Agrocampus UMR PEGASE1348Saint-Gilles35000 RennesFrance College of Bioengineering Henan University of TechnologyZhengzhou 450001China Jiangsu Youshi Biotechnology Development Co.Ltd. Suqian 223800JiangsuChina.

Background: Dietary fiber can be fermented in gut of pigs and the end products of fermentation were short-chain fatty acids(SCFA). The SCFA had positive effects on gut bacteria and host immune system. In addition, SCFA can provide a part of available energy for pigs. However, there were limited reports on the relationship between dietary fiber, gut bacteria, and energy metabolism. Therefore, this study investigated how dietary fiber and enzyme addition impacted energy metabolism by acting on the microbial community and SCFA.Methods: Wheat bran(WB) was added to the corn-soybean meal-based diet at the levels of 12% and 27%, and oat bran(OB) at 15% and 36%. One of each diet was supplemented with or without 5000 U/kg feed of xylanase, so a total of 10 diets were allotted to 60 growing pigs(initial body weight: 27.2 ± 1.2 kg) using a randomized complete block design. The experiment was conducted in 10 consecutive periods using 6 similar open-circuit respiration chambers. Each pig was used for one 20-day period. During each period, six pigs were allowed 14 d to adapt to the diets in metabolic cages followed by 6 d(from d 15 to d 20) in respiration chambers to measure heat production(HP).Results: Pigs fed 36% OB diets had greater(P < 0.05) nutrient digestibility and net energy(NE) values compared to those fed 27% WB diets. Apparent digestibility coefficients of dry matter(DM) and crude protein(CP) were lower(P < 0.05) in pigs fed 27% WB diets compared with those fed 12% WB diets. Enzyme addition improved(P < 0.05)the NE values(11.37 vs. 12.43 MJ/kg DM) in diets with 27% WB. Supplementation of xylanase did not affect NE values for basal diets, OB diets and 12%WB diets. Compared with diets with 36% OB, pigs fed 27% WB-based diets excreted more total SCFA, acetate and propionate(expressed as g/kg feed DM) in fecal samples of pigs(P < 0.05).Pigs in the WB diets had greater proportion of phylum Bacteroidetes while phylum Firmicutes were greater in pigs fed OB diets(P < 0.05). Pigs fed WB diets had greater(P < 0.05) abundance

关键词： Bacterial community Bacterial metabolites Dietary fiber Exogenous enzyme Net energy Pig

Self-Supervised Monocular Depth Estimation via Discrete Strategy and Uncertainty

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IEEE/CAA Journal of Automatica Sinica 2022年第7期9卷 1307-1310页

作者： Zhenyu Li junjun Jiang Xianming Liu School of Computer Science and Technology Harbin Institute of TechnologyHarbin 150001 Peng cheng Laboratory Shenzhen 518052China

Dear Editor,This letter is concerned with self-supervised monocular depth estimation.To estimate uncertainty simultaneously,we propose a simple yet effective strategy to learn the uncertainty for self-supervised monocular depth estimation with the discrete strategy that explicitly associates the prediction and the uncertainty to train the networks.Furthermore,we propose the uncertainty-guided feature fusion module to fully utilize the uncertainty information.Codes will be available at https://***/zhyever/Monocular-Depth-Estimation-Toolbox.Self-supervised monocular depth estimation methods turn into promising alternative trade-offs in both the training cost and the inference performance.However,compound losses that couple the depth and the pose lead to a dilemma of uncertainty calculation that is crucial for critical safety systems.To solve this issue,we propose a simple yet effective strategy to learn the uncertainty for self-supervised monocular depth estimation using the discrete bins that explicitly associate the prediction and the uncertainty to train the networks.This strategy is more pluggable without any additional changes to self-supervised training losses and improves model performance.Secondly,to further exert the uncertainty information,we propose the uncertainty-guided feature fusion module to refine the depth estimation.

关键词： estimation utilize uncertainty

RNA甲基化修饰作为肿瘤分子诊断新靶标的价值

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中华检验医学杂志 2024年第4期47卷 359-370页

作者：王成汪俊军南京大学医学院附属金陵医院&东部战区总医院检验科南京210002 南京中医药大学附属南京中医院(南京市中医院)医学检验科南京210022

恶性肿瘤已成为影响人类健康的主要原因,绝大多数尚缺乏高敏感度和特异度的诊断指标和治疗靶点。RNA甲基化修饰是近年来前沿研究热点,肿瘤组织、细胞和患者外周血中RNA甲基化修饰谱和修饰水平变化与肿瘤发生、发展、预后密切相关,具备... 详细信息

恶性肿瘤已成为影响人类健康的主要原因,绝大多数尚缺乏高敏感度和特异度的诊断指标和治疗靶点。RNA甲基化修饰是近年来前沿研究热点,肿瘤组织、细胞和患者外周血中RNA甲基化修饰谱和修饰水平变化与肿瘤发生、发展、预后密切相关,具备作为肿瘤精准诊断和治疗的靶标潜能。尽管目前RNA甲基化修饰检测方法学、作用机制研究和基于RNA甲基化修饰治疗药物的研发仍面临诸多挑战,但其作为肿瘤液体活检指标研究的新方向,展现出良好的临床价值和转化潜能,可为肿瘤的精准诊断、治疗靶标和药物研发提供新的策略和方向。

关键词：甲基化 RNA修饰肿瘤分子诊断技术

Energy Storage Technology in Multiple Microgrids:A Survey

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Energy Storage Technology in Multiple Microgrids:A Survey