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Catalytic Reaction Kinetics of Propylene Dimerization to 4-Methyl-1-Pentene Using Cu-K/K_(2)CO_(3) Solid Base Catalyst

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China Petroleum Processing & Petrochemical Technology 2024年第1期26卷 78-87页

作者： Jin Haibo Chai jing Yang Suohe he Guangxiang Ma Lei Guo Xiaoyan College of New Materials and Chemical Engineering Beijing Institute of Petrochemical Technology/Beijing Key Laboratory of Fuel Cleaning and Efficient Catalytic Emission Reduction TechnologyBeijing102617China

The catalysis technology of propylene dimerization to form 4-methyl-1-pentene(4MP1)using a Cu-K/K_(2)CO_(3) solid base catalyst is a well-known heterogeneous catalytic *** this study,the intrinsic kinetics of propylene dimerization were studied in a fixed-bed continuous *** and external diffusion during the dimerization reaction experiments were eliminated by adjusting the flow rate of the carrier gas and the particle size of the catalyst ***,the concentration changes of each substance at the outlet of the catalyst bed under different residence times were ***,the suitable reaction kinetics equations was derived using the Langmuir Hinshelwood-Hougen-Watson kinetic ***,the activation energy for each reaction involved in the dimerization reaction was *** activation energies of 4MP1,branched by-products,and 1-hexene were 115.0,150.8,and 177.4 kJ/mol,*** effect of process conditions on propylene dimerization with solid base catalysts was studied through kinetic model *** comparing the theoretical values obtained from the simulation with the experimental results,the applicability and accuracy of the kinetic model were verified.

关键词： propylene dimerization 4-methyl-1-pentene intrinsic kinetics surface reaction

A Blockchain-Based Proxy Re-Encryption Scheme with Conditional Privacy Protection and Auditability

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China Communications 2024年第7期21卷 267-277页

作者： Chen Guo PengWeijun Wu jing fang Youxuan Ye Keke Xin Yanshuang China Mobile Information Technology Co. LtdBeijing 100037China China Mobile Information Technology Co. LtdShenzhen 518048China

With the development of Internet of Things technology,intelligent door lock devices are widely used in the field of house *** the traditional housing leasing scenario,problems of door lock information disclosure,tenant privacy disclosure and rental contract disputes frequently occur,and the security,fairness and auditability of the housing leasing transaction cannot be *** solve the above problems,a blockchain-based proxy re-encryption scheme with conditional privacy protection and auditability is *** scheme implements fine-grained access control of door lock data based on attribute encryption technology with policy hiding,and uses proxy re-encryption technology to achieve auditable supervision of door lock information *** encryption technology and zero-knowledge proof technology are introduced to ensure the confidentiality of housing rent information and the fairness of rent *** construct a decentralized housing lease transaction architecture,the scheme realizes the efficient collaboration between the door lock data ciphertext stored under the chain and the key information ciphertext on the chain based on the blockchain and InterPlanetary File ***,the security proof and computing performance analysis of the proposed scheme are carried *** results show that the scheme can resist the chosen plaintext attack and has low computational cost.

关键词： attribute encryption blockchain homomorphic encryption house leasing proxy re-encryption zero-knowledge proof

Egg-associated secretions from the brown planthopper(Nilaparvata lugens)activate rice immune responses

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Insect Science 2024年第4期31卷 1135-1149页

作者： jing Li Shuai Li jing Li Xinyang Tan Zhichang Zhao Lei Jiang Ary A.Hoffmann Jichao fang Rui Ji Institute of Plant Protection Jiangsu Academy of Agricultural SciencesJiangsu Key Laboratory for Food and Safety-State Key Laboratory Cultivation Base of Ministry of Science and TechnologyNanjingChina College of Plant Protection Nanjing Agricultural UniversityNanjingChina School of Plant Protection Anhui Agricultural UniversityHefeiChina School of BioSciences Bio21 InstituteUniversity of MelbourneParkvilleVICAustralia Jiangsu Collaborative Innovation Center of Regional Modern Agriculture&Environmental Protection Huaiyin Normal UniversityHuaianJiangsu ProvinceChina

The brown planthopper(BPH,Nilaparvata lugens)is a notorious sap-sucking insect pest that damages rice(Oryza sativa)plants throughout *** BPH feeding,saliva enters rice plant tissues,whereas during oviposition egg-associated secretions(EAS)are deposited in damaged plant *** changes in rice to planthopper salivary effectors have been widely ***,the effects of EAS from planthopper on rice immunity remains largely *** this study,we found that both infestation of rice by gravid BPH female adults and treatment with the EAS elicited a strong and rapid accumulation of jasmonic acid(JA),JA-isoleucine,and hydrogen peroxide in *** enhanced plant defenses not only in rice but also in tobacco,and these impaired the performance of BPH on rice,as well as the performance of aphids and whiteflies on ***-throughput proteome sequencing of EAS led to 110 proteins being identified and 53 proteins with 2 or more unique peptides being *** proteins from BPH EAS were also found in the salivary proteome from herbivores,suggesting potential evolutionary conservation of effector functions across feeding and oviposition;however,others were only identified in EAS,and these are likely specifically related to *** findings point to novel proteins affecting interactions between planthoppers and rice during oviposition,providing an additional source of information for effector studies.

关键词： egg-associated secretion Nilaparvata lugens oviposition plant immunity proteome

Thermal stability improvement and microstructure optimization of high cobalt content Nd-Fe-B magnets via terbium grain boundary diffusion

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Journal of Rare Earths 2024年第8期42卷 1531-1538,I0004页

作者： Jiyuan Xu Ruiyang Meng jing Liu Jiateng Zhang Rui Han Yikun fang Shengzhi Dong Wei Li Division of Functional Materials Research Central Iron and Steel Research InstituteBeijing100081China

The substitution of Fe by Co in the 2:14:1 phase is an effective method to increase the Curie temperature and enhance the thermal stability of the Nd-Fe-B ***,the accumulation of Co ele ment at the grain boundaries(GBs) changes the GBs from nonmagnetic to ferromagnetic and causes the thinlayer GBs to become rare,In this paper,the method of diffusing Tb element was chosen to improve the microstructure and temperature stability of high-Co *** original sintered Nd_(28.5)Dy_(3)-CO_(x)e_(bal)M_(0.6)B_(i)(x=0,6 wt%,12 wt%;M = Cu,Al,Zr) magnets with different Co contents were diffused with Tb by grain boundary diffusion(GBD).After GBD,high-Co magnets exhibit more continuously distributed thin-layer GBs,and their thermal stability is significantly *** high-Co magnets(x=6 wt%),the absolute value of the temperature coefficient of coercivity decreases from 0.603%/K to0.508%/K in the temperature range of 293-413 K,that of remanence decreases from 0.099%/K to 0.091%/K,and the coercivity increases from 18.44 to 25.04 *** electron microscopy(TEM)characterization reveals that there are both the 1:2 phase and the amorphous phase in the high-Co magnet before and after GBD,EDS elemental analysis shows that Tb element is more likely to preferentially replace the rare earth elements in the 2:14:1 main phase than in the 1:2 phase and the amorphous *** concentration of Tb at the edge of the main phase is much higher than that in the 1:2phase and amorphous phase,which is beneficial to the improvement of the *** preferential replacement of Tb elements at the edge of the 2:14:1 phase and thin-layer GBs with a more continuous distribution are synergistically responsible for improving the thermal stability of high-Co *** study indicates that GBD is an effective method to improve the microstructure and thermal stability of high-Co magnets.

关键词： Nd-Fe-B magnets Coercivity Grain boundary diffusion Thermal stability Micro structure Rare earths

Serum 25-Hydroxyvitamin D Level Might Be a Useful Indicator of Disease Severity in Obese Children With Atopic Dermatitis:A Case-Control Study

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International Journal of Dermatology and Venereology 2024年第1期7卷 6-11页

作者： jing-jing Chen Xiao-Kai fang Xiu-Mei Liu Xiao-Chun Liu Xu Yao Department of Allergy and Rheumatology Hospital for Skin Diseases(Institute of Dermatology)Chinese Academy of Medical Sciences and Peking Union Medical CollegeNanjingJiangsu 210042China

Objective:To assess the relationship between the severity of atopic dermatitis(AD)in children of varying weight categories and their serum 25-hydroxyvitamin D[25(OH)D]***:The study population comprised 899 patients with AD and 854 age-and sex-matched *** Mann-Whitney U test and Kruskal-Wallis H tests were used to assess differences between groups,and Spearman correlation analysis was used to test ***:The 25(OH)D level in the AD group was M(Q_(25),Q_(75)),24.0(19.7,28.4)ng/mL,which was significantly lower than the control group(26.4[23.6,29.9]ng/mL;Z=-3.34,P=0.001).25(OH)D levels in children with AD were negatively correlated with body mass index(r=-0.30,Phere were statistically significant differences in 25(OH)D(H=18.46,Phe overweight AD group and 22.3(17.6,25.7)ng/mL in the obese AD group,which were significantly lower than those in the normal-weight AD group(24.7[20.4,25.5]ng/mL;P=0.003,P=0.004).25(OH)D levels were negatively correlated with SCORAD in obese AD patients(r=-0.25,P=0.010).Conclusion:Vitamin D insufficient or deficient is obvious in children AD *** 25(OH)D levels in the overweight/obese AD group are significantly lower than those in the normal-weight AD *** D level is negatively correlated with SCORAD in obese children with AD.

关键词： atopic dermatitis vitamin D disease severity index immunoglobulin E body mass index eosinophil children overweight/obese

Artificial intelligence for the detection of glaucoma with SD-OCT images:a systematic review and Meta-analysis

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International Journal of Ophthalmology(English edition) 2024年第3期17卷 408-419页

作者： Nan-Nan Shi jing Li Guang-Hui Liu Ming-fang Cao Department of Ophthalmology Affiliated People’s Hospital(Fujian Provincial People’s Hospital)Fujian University of Traditional Chinese MedicineFuzhou 350004Fujian ProvinceChina Eye Institute of Integrated Chinese and Western Medicine Fujian University of Traditional Chinese MedicineFuzhou 350004Fujian ProvinceChina

●AIM:To quantify the performance of artificial intelligence(AI)in detecting glaucoma with spectral-domain optical coherence tomography(SD-OCT)images.●METHODS:Electronic databases including PubMed,Embase,Scopus,ScienceDirect,ProQuest and Cochrane Library were searched before May 31,2023 which adopted AI for glaucoma detection with SD-OCT *** pieces of the literature were screened and extracted by two ***-analysis,Meta-regression,subgroup,and publication of bias were conducted by *** risk of bias assessment was performed in Revman5.4 using the QUADAS-2 tool.●RESULTS:Twenty studies and 51 models were selected for systematic review and *** pooled sensitivity and specificity were 0.91(95%CI:0.86–0.94,I2=94.67%),0.90(95%CI:0.87–0.92,I2=89.24%).The pooled positive likelihood ratio(PLR)and negative likelihood ratio(NLR)were 8.79(95%CI:6.93–11.15,I2=89.31%)and 0.11(95%CI:0.07–0.16,I2=95.25%).The pooled diagnostic odds ratio(DOR)and area under curve(AUC)were 83.58(95%CI:47.15–148.15,I2=100%)and 0.95(95%CI:0.93–0.97).There was no threshold effect(Spearman correlation coefficient=0.22,P>0.05).●CONCLUSION:There is a high accuracy for the detection of glaucoma with AI with SD-OCT *** application of AI-based algorithms allows together with“doctor+artificial intelligence”to improve the diagnosis of glaucoma.

关键词： artificial intelligence spectral-domain optical coherence tomography glaucoma Meta-analysis

Temporal assembly patterns of microbial communities in three parallel bioreactors treating low-concentration coking wastewater with differing carbon source concentrations

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Journal of Environmental Sciences 2024年第3期137卷 455-468页

作者： Weijia Li Yu Xia Na Li Jie Chang jing Liu Pei Wang Xuwen he School of Chemical and Environmental Engineering China University of Mining and Technology-BeijingBeijing 100083China

Carbon source is an important factor of biological treatment systems, the effects of which on their temporal community assembly patterns are not sufficiently understood *** this study, the temporal dynamics and driving mechanisms of the communities in three parallel bioreactors for low-concentration coking wastewater(CWW) treatment with differing carbon source concentrations(S0 with no glucose addition, S1 with 200 mg/L glucose addition and S2 with 400 mg/L glucose addition) were comprehensively studied. Highthroughput sequencing and bioinformatics analyses including network analysis and Infer Community Assembly Mechanisms by Phylogenetic bin-based null model(iCAMP) were used. The communities of three systems showed turnover rates of 0.0029~0.0034 every 15days. Network analysis results showed that the S0 network showed higher positive correlation proportion(71.43%) and clustering coefficient(0.33), suggesting that carbon source shortage in S0 promoted interactions and cooperation of microbes. The neutral community model analysis showed that the immigration rate increased from 0.5247 in S0 to 0.6478in S2. The iCAMP analysis results showed that drift(45.89%) and homogeneous selection(31.68%) dominated in driving the assembly of all the investigated microbial *** contribution of homogeneous selection increased with the increase of carbon source concentrations, from 27.92% in S0 to 36.08% in S2. The OTUs participating in aerobic respiration and tricarboxylic acid(TCA) cycle were abundant among the bins mainly affected by deterministic processes, while those related to the metabolism of refractory organic pollutants in CWW such as alkanes, benzenes and phenols were abundant in the bins dominated by stochastic processes.

关键词： Coking wastewater treatment Temporal dynamics Network analysis Deterministic processes Stochastic processes

MALDI coupled with laser-postionization and trapped ion mobility spectrometry contribute to the enhanced detection of lipids in cancer cell spheroids

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Chinese Chemical Letters 2024年第4期35卷 464-468页

作者： jing Chen Peisi Xie Pengfei Wu Yu he Zian Lin Zongwei Cai Ministry of Education Key Laboratory of Analytical Science for Food Safety and Biology Fujian Provincial Key Laboratory of Analysis and Detection Technology for Food SafetyCollege of ChemistryFuzhou UniversityFuzhou 350116China Department of Chemistry State Key Laboratory of Environmental and Biological AnalysisHong Kong Baptist UniversityHong KongChina College of Forestry Nanjing Forestry UniversityNanjing 210018China

Cancer cell spheroids(CCS) are a valuable three-dimensional cell model in cancer studies because they could replicate numerous characteristics of solid tumors. Increasing researches have used matrix-assisted laser desorption/ionization mass spectrometry imaging(MALDI-MSI) to investigate the spatial distribution of endogenous compounds(e.g., lipids) in CCS. However, only limited lipid species can be detected owing to a low ion yield by using MALDI. Besides, it is still challenging to fully characterize the structural diversity of lipids due to the existence of isomeric/isobaric species. here, we carried out the initial application of MALDI coupled with laser-postionization(MALDI-2) and trapped ion mobility spectrometry(TIMS) imaging in HCT116 colon CCS to address these challenges. We demonstrated that MALDI-2 is capable of detecting more number and classes of lipids in HCT116 colon CCS with higher signal intensities than MALDI. TIMS could successfully separate numerous isobaric/isomeric species of lipids in CCS. Interestingly, we found that some isomeric/isobaric species have totally different spatial distributions in colon CCS. Further MS/MS imaging analysis was employed to determine the compositions of fatty acid chains for isomeric species by examining disparities in signal intensities and spatial distributions of product ions. This work stresses the robust ability of TIMS and MALDI-2 imaging in analyzing endogenous lipids in CCS, which could potentially become powerful tools for future cancer studies.

关键词： Matrix-assisted laser desorption/ionization(MALDI) Mass spectrometry imaging MALDI coupled with laser-postionization Trapped ion mobility spectrometry Cancer cell spheroids

Three dimensional velocity model and its tectonic implications at China Seismic Experimental Site,eastern margin of the Tibetan Plateau

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Science China Earth Sciences 2024年第7期67卷 2268-2290页

作者： Jianping WU Yan CAI Wei WANG Weilai WANG Changzai WANG Lihua fang Yaning LIU jing LIU Institute of Geophysics China Earthquake AdministrationBeijing 100081China Beijing Baijiatuan Earth Science National Observation and Research Station Beijing 1095China Beijing Earthquake Agency Beijing 100080China

The China Seismic Experimental Site(CSES)is located at the intersection of the Tibetan Plateau,South China Block,and Indian Plate and has complex geological settings and intense crustal deformation,making it one of the most seismically active areas in Chinese mainland.A high-resolution,three-dimensional(3D)crust-mantle velocity structure is crucial for understanding seismotectonic environments,lithospheric deformation mechanisms,and deep dynamic *** first constructed a high-vertical-resolution 3D initial velocity model using the joint inversion of receiver functions and surface waves and then obtained a 3D P-and S-wave velocity model(CSES-VM1.0)with the highest lateral resolution of 0.25°for the CSES using double-difference *** to the limitations of the Sn observation data,the resolution of the S-wave velocity model in the lower crust and upper mantle was reduced,making it closer to the initial model provided by joint inversion.A comparison with explosive-source seismic data showed that the synthetic P-wave first-arrival travel times of the new model were closer to the observations than those of the previous velocity *** velocity cross-sections across the source areas of the 2022 Lushan MS6.1 and Ludian MS6.8 earthquakes reveal that the former earthquake occurred near a weak contact zone between the Tibetan Plateau and Sichuan Basin,and the rupture of the latter earthquake occurred in a granitic area,with the northern end blocked by rigid high-velocity bodies.A clear high-velocity anomaly zone is distributed along the western margin of the Yangtze Block,revealing the spatial distribution of Neoproterozoic intermediate-basic *** high-velocity zone significantly controls the morphology of fault zones and influences the rupture processes of major *** northeast-southwest and north-south trending high-velocity anomalies were found near Panzhihua,potentially related to Neoproterozoic and Middle-Late Permian intermediate

关键词： Eastern Tibetan Plateau China Seismic Experimental Site Yangtze Block Velocity model Double-difference tomography