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Photocatalytic vinyl radical-mediated multicomponent 1,4-/1,8-carboimination across alkynes and olefins/(hetero)arenes

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Science China Chemistry 2024年第2期67卷 558-567页

作者： Shan-Shan li Yu-Shi Jiang xue.ling Luo Xuming Ran Yuqiang li Dong Wu Cheng-xue pan Peng-Ju Xia School of Chemistry and Pharmaceutical Sciences Guangxi Normal UniversityGuilin541004China Shanghai Artificial Intelligence Laboratory Shanghai200433China The Institute for Advanced Studies Wuhan UniversityWuhan430064China

We developed a highly selective and efficient multicomponent transformation by utilizing alkynes and olefins/(hetero)arenes through photoinduced energy-transfer *** reaction involves the formation of three distinct chemical bonds,namely C(sp~3)–C(sp~2),C(sp~2)–C(sp~3),and C(sp~3)–N,in a single coordinated *** strategy used a vinyl radical-mediated radical relay approach under mild conditions,exhibiting a broad substrate scope(>70 examples),excellent functional-group tolerance,and remarkable regio-and *** the utilization of a combination of experimental techniques and density functional theory(DFT),we delved deeper into the mechanistic intricacies of this distinctive *** revealed that the selective radical addition to electron-deficient alkynes,rather than olefins,was governed by the inherent reactivity of alkyl *** discovery presented a highly effective approach for the synthesis of stereodefined multisubstituted alkenes.

关键词： alkyne-olefin coupling DFT studies regio-and anti-stereoselectivity multisubstituted alkenes

High-entropy sulfurization enables efficient non-noble metal-based NiCoFeCuS electrocatalyst for alkaline oxygen evolution reaction

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Particuology 2024年第10期93卷 180-185页

作者： pan Yang Mengxiang Sun Jingchuan Wang Jinfeng li Ruizhu Yang Yawei Hao li Qi lijun Yang xue.liu Institute of Materials China Academy of Engineering PhysicsJiangyou621908China State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao066004China Science and Technology on Surface Physics and Chemistry Laboratory Jiangyou621907China

Highly active and cost-effective oxygen evolution reaction electrocatalysts have become essential to replace commercial electrocatalysts that rely on rare noble ***-entropy sulfide nanomaterials,characterized by abundant randomly distributed elements and inherent stability,possess significant potential for ***,challenges such as uneven composition,partial oxidation,or imprecise synthesis control still remain in the materials ***,a simple and effective two-step hydrothermal method was employed to synthesize NiCoFeCuS nanoparticles supported on foam nickel *** the catalytic active sites produced by electron density redistribution in high-entropy and sulfurization,NiCoFeCuS exhibits excellent alkaline OER performance,with an overpotential of 261 mV and a Tafel slope of 57.97 mV dec^(−1) at the current density of 10 mA cm^(−2),which is only 88%of commercial RuO_(2) without any noble metals.

关键词： High-entropy Sulfurization NiCoFeCuS electrocatalyst Oxygen evolution reaction Overpotentials

Insider threat detection approach for tobacco industry based on heterogeneous graph embedding

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High Technology Letters 2024年第2期30卷 199-210页

作者：季琦 li Wei pan Bailin xue Hongkai QIU Xiang Hangzhou Cigarette Factory China Tobacco Zhejiang Industrial Co.Ltd.Hangzhou 310024P.R.China Information Center China Tobacco Zhejiang Industrial Co.Ltd.Hangzhou 310024P.R.China College of Information Engineering Zhejiang University of TechnologyHangzhou 310014P.R.China

In the tobacco industry,insider employee attack is a thorny problem that is difficult to *** solve this issue,this paper proposes an insider threat detection method based on heterogeneous graph ***,the interrelationships between logs are fully considered,and log entries are converted into heterogeneous graphs based on these ***,the heterogeneous graph embedding is adopted and each log entry is represented as a low-dimensional feature ***,normal logs and malicious logs are classified into different clusters by clustering algorithm to identify malicious ***,the effectiveness and superiority of the method is verified through experiments on the CERT *** experimental results show that this method has better performance compared to some baseline methods.

关键词： insider threat detection advanced persistent threats graph construction heterogeneous graph embedding

Micro-nanoarchitectonic of aluminum-hydrogel propellant with static stability and dynamic rheology

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Frontiers of Chemical Science and Engineering 2024年第4期18卷 87-96页

作者： Huiyan Guo Huaiyu li Hongzhi Zhang Lun pan Chengxiang Shi Kang xue Xiangwen Zhang Ji-Jun Zou Key Laboratory for Advanced Fuel and Propellant of Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China

The aluminum-water system is a promising propellant due to high energy and low signal characteristics,and the gel form is easier to store and *** this work,hydrogels of water and aluminum particles were prepared using the low-molecular-weight gellant *** various physical properties of gel systems,including the water loss rate,phase transition temperature,and centrifugal stability at different gellant and aluminum contents,were *** properties were assessed through shear thinning tests,thixotropy tests,strain sweep analysis,and frequency sweep *** microstructure of the gel was obtained through scanning electron microscopy *** results show that the aluminum-hydrogel network structure is composed of micron-scale aluminum and agarose nanosheets,and the unique micro-nanostructure endows the gel with excellent mechanical strength and thermal stability,which improve with increasing gellant and aluminum ***,the gel with 2% agarose and 20% aluminum had the best performance;the storage modulus reached 90647 Pa,which was within the linear viscoelastic region,and the maximum withstand pressure was 111.2 kPa,which was 118.8% greater than that of the pure ***,the gel demonstrates remarkable shear thinning behavior and can undergo gel-sol transformation upon shearing or heating to exceeding 114℃.

关键词： aluminum-water propellant gelled propellant rheological property mechanical strength

Photoinduced transposed Paternò-Büchi reaction for effective synthesis of high-performance jet fuel

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Chinese Journal of Chemical Engineering 2024年第3期67卷 39-48页

作者： Jinxiu Hu Xianlong liu Yi liu Kang xue Chengxiang Shi Xiangwen Zhang li Wang Ji-Jun Zou Lun pan Key Laboratory for Green Chemical Technology of the Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China Zhejiang Institute of Tianjin University Ningbo 315201China Collaborative Innovative Center of Chemical Science and Engineering(Tianjin) Tianjin 300072China

High-energy-density fuels are important for volume-limited aerospace vehicles,but the increase in fuel energy density always leads to poor cryogenic ***,we investigated the transposed Paternò-Büchi reaction of biomass cyclic ketone and cyclic alkene to synthesize a new kind of alkyl-substituted polycyclic hydrocarbon fuel with high energy density and good cryogenic *** triplet-energy-quenching results and phosphorescent emission spectra reveal the sensitization mechanism of the reaction,including photosensitizer excitation,triplettriplet energy transfer,cyclization,and relaxation,and the possible reaction path was revealed by the density functional theory(DFT)*** reaction conditions of photosensitizer type and addition,molar ratio of substrates,reaction temperature,and incident light intensity were optimized,with the target product yield achieving 65.5%.Moreover,the reaction dynamics of the reaction rate versus the light intensity are *** the hydrogenation-deoxygenation reaction,three fuels with a high density of 0.864-0.938 g·ml^(-1) and a low freezing point of<-55℃ are *** work provides a benign and effective approach to synthesize high-performance fuels.

关键词： High-energy-density fuel Transposed Patern-oeBüchi reaction Kinetics Bioenergy Photochemistry

Association between the cumulative triglyceride-glucose index and the recurrence of atrial fibrillation after radiofrequency catheter ablation

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Journal of Geriatric Cardiology 2024年第2期21卷 200-210页

作者： Qing YAN Jia-Qi liANG Yi-De YUAN Yuan li Jia-li FAN Wen-Huan WU pan XU Jia-Hong xue Department of Cardiovascular Medicine the Second Affiliated Hospital of Xi’an Jiaotong UniversityShaanxiChina Department of Cardiovascular Medicine Zichang People’s HospitalShaanxiChina Department of Ultrasound Xijing HospitalAir Force Military Medical UniversityShaanxiChina

BACKGROUND Triglyceride-glucose(TyG)index values are a new surrogate marker for insulin *** study aimed to explore the relationship between cumulative TyG index values and atrial fibrillation(AF)recurrence after radiofrequency catheter ablation(RFCA).METHODS A total of 576 patients with AF who underwent RFCA at the Second Affiliated Hospital of Xi'an Jiaotong University were included in this *** participants were grouped based on cumulative TyG index values tertiles within 3 months after *** regression and restricted cubic spline analyses were used to determine the relationship between cumulative TyG index values and AF *** predictive value of all risk factors was assessed by receiver operating curve *** There were 375 patients completed the study(age:63.23±10.73 years,64.27%male).The risk of AF recurrence increased with increasing cumulative TyG index values *** adjusting for potential confounders,patients in the medium cumulative TyG index group[hazard ratio(HR)=4.949,95%CI:1.778–13.778,P=0.002]and the high cumulative TyG index group(HR=8.716,95%CI:3.371–22.536,Pline regression model also showed an increased risk of AF recurrence with increasing cumulative TyG index *** considering cumulative TyG index values,left atrial diameter,and lactate dehydrogenase levels as a comprehensive factor,the model could effectively predict AF recurrence after RFCA[area under the curve(AUC)=0.847,95%CI:0.797–0.897,P<0.001].CONCLUSIONS Cumulative TyG index values were a risk factor for AF recurrence after *** longitudinal TyG index values may assist with optimized for risk stratification and outcome prediction for AF recurrence.

关键词： atrial fibrillation index

The Al_(2)O_(3)and Mn/Al_(2)O_(3)sorbents highly utilized in destructive sorption of NF_(3)

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Chinese Journal of Chemical Engineering 2024年第1期65卷 54-62页

作者： Yanfei pan Hejian li li Zheng Xiufeng Xu School of Chemistry and Chemical Engineering Yantai UniversityYantai 264005China

NF_(3)is commonly used as an etching and cleaning gas in semiconductor industry,however it is a strongly greenhouse ***,the destruction of disposal NF_(3)is an urgent task to migrate the greenhouse *** the technologies for NF_(3)abatement,the destructive sorption of NF_(3)over metal oxides sorbents is an effective ***,the search for a highly reactive and utilized sorbent for NF_(3)destruction is in great *** this work,AlOOH supported on carbon-sphere(AlOOH/CS)as precursors were synthesized hydrothermally and heat-treated to prepare the Al_(2)O_(3)*** influence of AlOOH/CS hydrothermal temperatures on the reactivity of derived Al_(2)O_(3)sorbents for NF_(3)destruction was investigated,and it is shown that the Al2O3 from AlOOH/CS hydro-thermalized at 120℃is superior to ***,the optimized Al_(2)O_(3)was covered by Mn(OH)x to prepare Mn/Al_(2)O_(3)sorbents via changing hydrothermal temperatures and Mn *** results show that the Mn/Al_(2)O_(3)sorbents are more utilized than bare Al_(2)O_(3)in NF_(3)destructive sorption due to the promotional effect of Mn_(2)O_(3)as surface layer on the fluorination of Al_(2)O_(3)as substrate,especially the optimal 5%Mn/Al2O3(160℃)exhibits a utilization percentage as high as 90.4%,and remarkably exceeds all the sorbents reported so *** findings are beneficial to develop more efficient sorbents for the destruction of NF_(3).

关键词： Greenhouse gas NF_(3)destructive sorption Sorbents Al_(2)O_(3) Mn/Al_(2)O_(3) Reactivity

FlowGANAnomaly: Flow-Based Anomaly Network Intrusion Detection with Adversarial Learning

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Chinese Journal of Electronics 2024年第1期33卷 58-71页

作者： Zeyi li pan WANG Zixuan WANG School of Computer Science Nanjing University of Posts and Telecommunications School of Modern Posts Nanjing University of Posts and Telecommunications School of Internet of Things Nanjing University of Posts and Telecommunications

In recent years, low recall rates and high dependencies on data labelling have become the biggest obstacle to developing deep anomaly detection(DAD) techniques. Inspired by the success of generative adversarial networks(GANs) in detecting anomalies in computer vision and imaging, we propose an anomaly detection model called Flow GANAnomaly for detecting anomalous traffic in network intrusion detection systems(NIDS). Unlike traditional GAN-based approaches, which are composed of a flow encoder, a convolutional encoder-decoder-encoder, a flow decoder and a convolutional encoder, the architecture of this model consists of a generator(G) and a discriminator(D).Flow GANAnomaly maps the different types of traffic feature data from separate datasets to a uniform feature space,thus can capture the normality of network traffic data more accurately in an adversarial manner to mitigate the problem of the high dependence on data labeling. Moreover, instead of simply detecting the anomalies by the output of D, we proposed a new anomaly scoring method that integrates the deviation between the output of two Gs’ convolutional encoders with the output of D as weighted scores to improve the low recall rate of anomaly detection. We conducted several experiments comparing existing machine learning algorithms and existing deep learning methods(Auto Encoder and VAE) on four public datasets(NSL-KDD, CIC-IDS2017, CIC-DDo S2019, and UNSW-NB15). The evaluation results show that Flow GANAnomaly can significantly improve the performance of anomaly-based NIDS.

关键词： Deep learning Machine learning algorithms Computational modeling Network intrusion detection Imaging Telecommunication traffic Generative adversarial networks

A numerical simulation strategy for a compressor’s underlying axisymmetric characteristic and its application in body force model

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Chinese Journal of Aeronautics 2024年第8期37卷 79-90页

作者： Shijie liU Tianyu pan Qiushi li School of Energy and Power Engineering Beihang UniversityBeijing 100191China Research Institute of Aero-Engine Beihang UniversityBeijing 100191China Key Laboratory of Fluid and Power Machinery Ministry of EducationXihua UniversityChengdu 610039China

Accurate prediction of the aerodynamic response of a compressor under inlet distortion is crucial for next-generation civil aircraft,such as Boundary Layer Ingestion(Bli)silent ***,research on the Body Force(BF)model plays a significant role in achieving this ***,distorted inlet airflow can lead to varying operating conditions across different spatial locations of the compressor,which may cause some regions to operate outside the stability ***,the accuracy of BF model simulations might be *** address this issue,this paper proposes a numerical simulation strategy for acquiring the steady axisymmetric three-dimensional flow field of a compressor operating at low mass flow rates,which is known as the Underlying Axisymmetric Pressure Rise Characteristic(UAPRC).The proposed simulation accounts for two different rotor speeds of a transonic compressor and identifies initial positions in the flow field where deterioration occurs based on prior experimental ***,simulation results are incorporated into the BF model to replicate hub instability observed in *** results demonstrate that this strategy provides valid predictions of the UAPRC of the compressor,thereby addressing the limitations associated with the BF model.

关键词： Compressor partial instability Performance at low mass flow rates Underlying axisymmetric pressure rise characteristic Novel simulation strategy Body force model