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Development of Hydrocracking Catalyst to Produce High Quality Clean Middle Distillates

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China Petroleum Processing & Petrochemical Technology 2004年第4期6卷 19-23页

作者： Zhang Xuejun 1.2 Zhang zhihua1.2(1. Institute of Daqing Petrochemical Company, Daqing 1.371. 2. School of Chemistry & Chemical Engineering, University of Petroleum,Dongying 257061. Inst. of Daqing Petrochem. Company Daqing 163714 China Sch. of Chem. and Chem. Engineering University of Petroleum Dongying 257061 China

A novel hydrocracking Ni-W binary catalyst was tentatively designed and prepared by means ofimpregnation on mixed supports of modified Y zeolite and amorphous aluminosilicate . The structure andproperties of catalyst were extensively characterized by XRD, NH3-TPD, IR and XRF techniques. The perfor-mance of catalyst was evaluated by a 1.0-ml hydrogenation laboratory test unit with two single-stage fixed-bedreactors connected in series. The characterization results showed that the catalyst has a developed and con-centrated mesopores distribution, suitable acid sites and acid strength distribution, and uniform and highdispersion of metal sites. Under a high conversion rate of 73.8% with the >350℃ feedstock, a 98.1.% of C5+yield and 83.5% of middle distillates selectivity were obtained. The yield of middle distillates boiling between1.0℃and 370℃ was 68.70m% and its quality could meet the WWFC category III specification. It means thatthis catalyst could be used to produce more high quality clean middle distillates derived from heavy oilhydrocracking. The potential aromatic content of heavy naphtha from 65℃ to 1.0℃ was 37.5m%. The BMCIvalue of >370℃ tail oil was 6.6. The heavy naphtha and tail oil are premium feedstocks for catalytic reformingand steam cracker units.

关键词： hydrocracking Ni-W binary catalyst clean middle distillate WWFC categoryIII specification

Atmospheric correction for China's coastal water colorremote sensing

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Acta Oceanologica Sinica 2001年第3期20卷 343-354页

作者： PanDelu, Mao zhihua 1. Laboratory of Ocean Dynamic Processes and Satellite Oceanography of State Oceanic Administration, Hangzhou 31.01., China 2. Laboratory of Submarine Geosciences of State Oceanic Administration, Hangzhou 31.01., China Lab. Ocean Dynamic Processes State Oceanic Administation Hangzhou 310012 China Laboratory of Submarine Geosciences State Oceanic Administation Hangzhou 310012 China

The space satellite programs, such as CZCS/Nimbus - 7, VHRSR/FY - 1. OCFS/ ADEOS and SeaWiFS/SeaStar, have demonstrated and proven that remote sensing is a powerful tool for understanding the spatial and temporal ocean color distribution. In general, there are two main techni-cal keys in the processing ocean color satellite data. They are the atmospheric correction and the inver-sion of water-leaving radiance into water constituents (such as chlorophyll, suspended material and yel low substance) quantitatively. The SeaWiFS (sea-viewing wide field-of-view sensor) atmospheric correc-tion algorithm for China's coastal waters is discussed. First, the major advantages of SeaWiFS are introduced. Second, in view of the problems of the SeaDAS algorithm applying in China' s coastal waters, the local atmospheric correction algorithms are discussed and developed. Finally, the advantages of the local algorithms are presented by the compari-son of the results from two different algorithms.

关键词： Atmospheric correction water-leaving radiance

Design and identification of a double-acting piezoelectric-hydraulic hybrid actuator

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Chinese Journal of Aeronautics 2024年第3期37卷 456-467页

作者： Junjian ZHANG zhihua FENG Key Laboratory of Precision Scientific Instrumentation of Anhui Higher Education Institutes University of Science and Technology of ChinaHefei 230026China

Traditional single-acting piezoelectric-hydraulic hybrid actuators usually have the problem of inertial force caused by flow pulsation of the liquid,which degrades their output *** suppress or solve the associated inertial force and enhance its output capabilities,this paper proposes a new type of double-acting piezoelectric-hydraulic hybrid actuator with four check valves acting as mechanical *** new hybrid actuator was fabricated and its output performance was *** the voltage is 700 Vp-pand the bias pressure is 2 MPa,the pulsation ratesδof the new actuator at 400 Hz,500 Hz and 600 Hz are 2.29,2.08 and 1.78,respectively,whileδof the single-acting hybrid actuator under the same conditions are 1..98,1..05 and ***,the liquid pulsation rate of the new hybrid actuator is significantly reduced,which is beneficial for improving the flow uniformity and weakening the influence of inertial force on the hybrid *** strategy ultimately leads to a maximum no-load velocity of 1.8.1.mm/s at 600 Hz and a maximum blocking force of 1.1.N at 450 Hz for the new hybrid *** addition,this strategy has the potential to be used in other electrohydrostatic actuators to improve their performance.

关键词： Double-acting Flow pulsation Inertial force Piezoelectric actuators Piezoelectric devices Piezoelectric hydraulic actuation Piezoelectric pump

Stability and bifurcation analysis of a size-stage-structured cooperation model

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International Journal of Biomathematics 2024年第1期17卷 61-80页

作者： Yajing Li zhihua Liu Laboratory of Mathematics and Compler Systems(Ministry of Education)School of Mathematical Sciences Beijing Normal University Beijing 1.0875 P.R.China

In this paper,we propose a size-stage-structured cooperation model which has two distinct life stages in facultative *** primary feature of this model is to consider size structure,stage structure and obligate and facultative symbiosis at the same time in a cooperation *** use the method of characteristic to show that this new model can be reduced to a threshold delay equations(TDEs)model,which can be further transformed into a functional differential equations(FDEs)model by a simple change of *** simplification allows us to apply the classical theory of FDEs and establish a set of sufficient conditions to investigate the qualitative analysis of solutions of the FDEs model,including the global existence and uniqueness,positivity and ***'s more,we use the geometric criteria to get the conclusions about stability and Hopf bifurcation of positive equilibrium because the coefficients of the characteristic equation depend on the bifurcation ***,numerical simulations are carried out as supporting evidences of our analytical *** results show that the presence of size structure and stage structure plays an important role in the dynamic behavior of the model.

关键词： Cooperation model size-structured threshold-type delay stability bifurcation

The Structure Entropy of Social Networks

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Journal of Systems Science & Complexity 2024年第3期37卷 1147-1162页

作者： LI Zhenpeng YAN zhihua YANG Jian TANG Xijin School of Electronics and Information Engineering Taizhou UniversityLinhai 317000China Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China Yunnan Key Laboratory of Smart City in Cyberspace Security Yuxi Normal UniversityYuci 653100China University of Chinese Academy of Sciences Beijing 100039China

Micro triadic structure is an important motif and serves the building block of complex *** this paper,the authors define structure entropy for a social network and explain this concept by using the coded triads proposed by Davis and Leinhardt in *** proposed structure entropy serves as a new macro-evolution index to measure the network’s stability at a given *** analysis of real-world network structure entropy discloses rich information on the mechanism that yields given triadic motifs frequency *** paper illustrates the intrinsic link between the micro dyadic/triadic motifs and network structure ***,the authors find that the high proportion of reciprocity and transitivity results in the emergence of hierarchy,order,and cooperation of online social networks.

关键词： Dyadic and triadic motifs network structure entropy reciprocity and transitivity

An Industrial Intrusion Detection Method Based on Hybrid Convolutional Neural Networks with Improved TCN

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Computers, Materials & Continua 2024年第1期78卷 411-433页

作者： zhihua Liu Shengquan Liu Jian Zhang College of Computer Science and Technology Xinjiang UniversityXinjiang Uygur Autonomous RegoinUrumqi830000China

Network intrusion detection systems(NIDS)based on deep learning have continued to make significant ***,the following challenges remain:on the one hand,simply applying only Temporal Convolutional Networks(TCNs)can lead to models that ignore the impact of network traffic features at different scales on the detection *** the other hand,some intrusion detection methods considermulti-scale information of traffic data,but considering only forward network traffic information can lead to deficiencies in capturing multi-scale temporal *** address both of these issues,we propose a hybrid Convolutional Neural Network that supports a multi-output strategy(BONUS)for industrial internet intrusion ***,we create a multiscale Temporal Convolutional Network by stacking TCN of different scales to capture the multiscale information of network ***,we propose a bi-directional structure and dynamically set the weights to fuse the forward and backward contextual information of network traffic at each scale to enhance the model’s performance in capturing the multi-scale temporal features of network *** addition,we introduce a gated network for each of the two branches in the proposed method to assist the model in learning the feature representation of each *** experiments reveal the effectiveness of the proposed approach on two publicly available traffic intrusion detection datasets named UNSW-NB1. and NSL-KDD with F1.score of 85.03% and 99.31.,respectively,which also validates the effectiveness of enhancing the model’s ability to capture multi-scale temporal features of traffic data on detection performance.

关键词： Intrusion detection industrial internet channel spatial attention multiscale features dynamic fusion multi-output learning strategy

Kinetics and mechanism of propylene hydro-oxidation to acrolein on Au catalysts

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Nano Research 2024年第1期17卷 354-363页

作者： Wei Du zhihua Zhang Nan Song Xuezhi Duan Xinggui Zhou State Key Laboratory of Chemical Engineering School of Chemical EngineeringEast China University of Science and TechnologyShanghai 200237China

Propylene epoxidation by H_(2)and O_(2)to propylene oxide(PO)over the Au-Ti bifunctional catalysts,as an ideal reaction for PO production,has attracted great *** the mechanism of acrolein formation is of great importance for understanding the mechanism of molecular oxygen activation and the formation of hydroperoxo species on the Au ***,we investigate the reaction mechanism of propylene oxidation to acrolein on the Au/uncalcined TS-1.Au/TS-1.B)catalyst through a combination of multiple characterization,H_(2)/D_(2)exchange,kinetics experiment,and *** Ti sites are found to be non-essential to acrolein ***,the acrolein formation on the Au/TS-1.B catalyst is confirmed to be promoted by H_(2)through hydroperoxo species formation,which includes two main steps:propylene dehydrogenation to*C_(3)H_(5)with the aid of*OOH species,and*C_(3)H_(5)oxidation by*OOH to *** latter step is determined to be the rate-determining step because the corresponding kinetics model gives the best description for experimental *** work not only provides kinetics insights for the propylene hydro-oxidation to acrolein on the Au-Ti bifunctional catalysts,but also facilitates the rational design of Au catalysts with high activity and selectivity in the direct propylene epoxidation with H_(2)and O_(2).

关键词： kinetics mechanism gold acrolein hydro-oxidation

Design strategy and relevant flow mechanisms of highly loaded 3D compressor tandem cascades

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Chinese Journal of Aeronautics 2024年第7期37卷 220-235页

作者： Xiaochen MAO Yunyu WANG zhihua DING Hao CHENG Bo LIU School of Power and Energy Northwestern Polytechnical UniversityXi’an 710129China The National Key Laboratory of Science and Technology on Aerodynamic Design and Research Xi’an 710129China Xi’an Thermal Power Research Institute Co.Ltd Xi’an 710072China

To investigate the design strategy of highly loaded tandem cascades at both the midspan and endwall,the overall performance and flow mechanisms of four typical tandem cascades based on the optimization were analyzed from multiple perspectives *** results show that the interference effects on the Front Blade(FB)and Rear Blade(RB)should not be overlooked during the design phase,and the design strategies at the midspan and endwall are completely *** the midspan,the optimization aims to increase the interference effects and the strength of the gap jet while maintaining the same load on the FB and ***,the endwall optimal airfoil exhibits weakening interference effects,advancement of the gap jet location,and load transfer from the FB to *** further analysis of flow characteristics,the midspan optimal airfoil is beneficial for inhibiting the low-energy fluid from interacting with the suction surface of RB under the design condition,but results in earlier occurrence of corner *** endwall optimal airfoil helps suppress the development of the secondary flow and delay the onset of corner ***,by combining the benefits of these two design approaches,additional forward sweep effects are achieved,further enhancing the performance of the tandem cascade.

关键词： Tandem cascade Interference effect Vortex structure Load split Compressor

Unstructured Big Data Threat Intelligence Parallel Mining Algorithm

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Big Data Mining and Analytics 2024年第2期7卷 531-546页

作者： zhihua Li Xinye Yu Tao Wei Junhao Qian School of Artificial Intelligence and Computer Science Jiangnan UniversityWuxi 214122China School of IoT Engineering Jiangnan UniversityWuxi 214122China

To efficiently mine threat intelligence from the vast array of open-source cybersecurity analysis reports on the web,we have developed the Parallel Deep Forest-based Multi-Label Classification(PDFMLC)***,open-source cybersecurity analysis reports are collected and converted into a standardized text ***,five tactics category labels are annotated,creating a multi-label dataset for tactics *** the limitations of low execution efficiency and scalability in the sequential deep forest algorithm,our PDFMLC algorithm employs broadcast variables and the Lempel-Ziv-Welch(LZW)algorithm,significantly enhancing its acceleration ***,our proposed PDFMLC algorithm incorporates label mutual information from the established dataset as input *** captures latent label associations,significantly improving classification ***,we present the PDFMLC-based Threat Intelligence Mining(PDFMLC-TIM)*** results demonstrate that the PDFMLC algorithm exhibits exceptional node scalability and execution ***,the PDFMLC-TIM method proficiently conducts text classification on cybersecurity analysis reports,extracting tactics entities to construct comprehensive threat *** a result,successfully formatted STIX2.1.threat intelligence is established.

关键词： unstructured big data mining parallel deep forest multi-label classification algorithm threat intelligence