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A Novel ISSA–DELM Model for Predicting Rock Mass Permeability

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Computer Modeling in Engineering & Sciences 2024年第9期140卷 2825-2848页

作者： Chen Xing Leihua yao Yingdong wang School of Engineering and Technology China University of Geosciences(Beijing)Beijing100083China Beijing Engineering Corporation Limited Beijing100024China

In pumped storage projects,the permeability of rock masses is a crucial parameter in engineering design and *** rock mass permeability coefficient(K)is influenced by various geological parameters,and previous studies aimed to establish an accurate relationship between K and geological *** study uses the improved sparrow search algorithm(ISSA)to optimize the parameter settings of the deep extreme learning machine(DELM),constructing a prediction model with flexible parameter selection and high ***,the Spearman method is applied to analyze the correlation between geological parameters.A sample database is built by comprehensively selecting four geological indexes:burial depth,rock quality designation(RQD),fracture density characteristic index(FD),and rock mass integrity designation(RID).Hence,the defects of the sparrow search algorithm(SSA)are enhanced using the improved strategy,and the initial input weights of the DELM are ***,the proposed ISSA–DELM model is employed to predict the permeability coefficient of rock mass in the entire study *** results showed that the predictive performance of the model is superior to that of the DELM and SSA–***,this model successfully provides insights into the distribution characteristics of rock mass permeability at engineering sites.

关键词： ISSA DELM rock mass permeability coefficient geological parameter correlation analysis

Ligand-dependent aggregation-enhanced photoacoustic of atomically precise metal nanocluster

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Aggregate

Aggregate 2024年第1期5卷 196-203页

作者： Changlin Zhou Meng wang Qiaofeng yao yu Zhou Chuantao Hou Jianfei Xia Zonghua wang Jishi Chen Jianping Xie College of Chemistry and Chemical Engineering Shandong Sino-Japanese Center for Collaborative Research of Carbon NanomaterialsInstrumental Analysis Center of Qingdao UniversityQingdao UniversityQingdaoP.R.China Tianjin Key Laboratory of Molecular Optoelectronic Sciences Department of ChemistrySchool of ScienceTianjin UniversityTianjinP.R.China Qingdao Boting Hydrogen Age Ocean Technol R&D Ctr. Qingdao Boting Technol Co.Ltd.Shandong Hydrogen Times Marine Technology Co.Ltd.QingdaoP.R.China Department of Chemical and Biomolecular Engineering National University of SingaporeSingapore Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityBinhai New CityFuzhouP.R.China

Atomically precise metal nanoclusters(MNCs),as a potential type of photoacoustic(PA)contrast agent,are limited in application due to their low PA conversion efficiency(PACE).Here,with hydrophilic Au25SR18(SR=thiolate)as model NCs,we present a result that weakly polar solvent induces aggregation,which effectively enhances PA intensity and *** PA intensity and PACE are highly dependent on the degree of aggregation,while the aggregation-enhanced PA intensity(AEPA)positively correlates to the protected *** an AEPA phenomenon indicates that aggregation actually accelerates the intramolecular motion of Au NCs,and enlarges the proportion of excited state energy dissipated through vibrational *** result conflicts with the restriction of intramolecular motion mechanism of aggregation-induced *** experiments show that the increased energy of AEPA originates from the aggregation inhibiting the intermolecular energy transfer from excited Au NCs to their surrounding medium molecules,including solvent molecule and dissolved oxygen,rather than restricting radiative *** study develops a new strategy for enhancing the PA intensity of Au NCs,and contributes to a deeper understanding of the origin of the PA signal and the excited state energy dissipation processes for MNCs.

关键词： aggregation-enhanced photoacoustic gold nanocluster intermolecular excited state energy transfer intramolecular motion ligand effect

Identification of two compound heterozygous GNRHR mutations in two siblings with congenital hypogonadotropic hypogonadism

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Asian Journal of Andrology 2024年第1期26卷 120-122页

作者： Xiao-Bin wang Ping Chen Xue-Er yu Zu-Liang yao Ting-Chao Guo Bo-Chen Pan Center for Reproductive Medicine Department of Obstetrics and GynecologyShengjing Hospital of China Medical UniversityShenyang 110004China NuProbe Shanghai 200433China Urology Surgery of The Affiliated Reproductive Hospital of China Medical University and Liaoning Key Laboratory of Reproductive Health Liaoning Research Institute of Family Planning(The Affiliated Reproductive Hospital of China Medical University)Shenyang 110031China NHC Key Laboratory of Reproductive Health and Medical Genetics China Medical UniversityShenyang 110122China

DearEditor,Congenital hypogonadotropic hypogonadism(CHH)is a rare genetic disease characterized by gonadotropin-releasing hormone(GnRH)deficiency or insufficiency and normal hypothalamic-pituitary structures,resulting in defective sexual maturation or/and infertility.!CHH presents as a variety of nonreproductive phenotypes,such as renal hypoplasia,dental hypoplasia,or oculomotor abnormalities.

关键词： pogon compound ism

Enhancement of catalytic activity for hydrogenation of nitroaromatic by anionic metal-organic framework

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Chinese Chemical Letters 2024年第3期35卷 144-148页

作者： Qi Wu Anyang Li Ruibo He Yaxi Wu Lei Hou Guoping Yang Wenyan Zhang yao-yu wang Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education College of Chemistry&Materials ScienceNorthwest UniversityXi'an 710127China

Nitroaromatic hydrogenation catalysis without precious metals remains a longstanding *** rate of electron transfer is the crucial factor affecting hydrogenation ***,an ionic Cd-based metal-organic framework(I-Cd-MOF)exhibiting a unique structure with one-dimensional(1D)opening nanochannels and good electron transfer ability was synthesized for catalyzing hydrogenation of 4-nitrophenol(4-NP).The catalytic activity of the unique I-Cd-MOF without noble metals is detected,which is higher than most reported noble metal ***,the reaction rate of I-Cd-MOF(4.28 min^(-1))is about 47.6 times higher than that of the Cd-based neutral MOF(N-Cd-MOF)with the similar crystalline *** chromatograph mass spectrometer(LC-MS)and theoretical results demonstrate that 4-NP and five intermediates are stabilized in the channels of I-Cd-MOF,which increases the possibility of contact with H^*and H_(2)g enerated at the Cd *** I-Cd-MOF was extended to other nitroaromatic hydrogenation catalysis,which still displays excellent *** importantly,the I-MOF@Filter membrane was successfully constructed for continuous hydrogenation catalytic reactions,which maintains a high catalytic performance after 7 cycles of recycling without *** work fills in the application of the I-MOFs in hydrogenation catalytic reactions and provides an effective way for the rapid and green degradation of nitroaromatic compounds.

关键词： Anions Metal-organic frameworks Catalysis Electron transfer Hydrogen production

Synergistic silver-mediated and palladium-catalyzed nondirected olefination of aryl C–H bond: quick access to multi-substituted aryl olefins

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Science China Chemistry 2024年第3期67卷 882-889页

作者： Jian yao Lili Shao Xiaohong Huo Xiaoming wang Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs Frontiers Science Center for Transformative MoleculesSchool of Chemistry and Chemical EngineeringShanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Organometallic Chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 20032China School of Chemistry and Materials Science Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China

Transition metal-catalyzed olefination of aryl C-H bond is a powerful tool for the synthesis of alkenes. While the Pd-catalyzed oxidative C-H olefination of arenes, also known as Fujiwara-Moritani reaction, has been established as one of the most efficient methods, the substrates are largely limited to terminal olefins with electron-withdrawing group(s). Herein, we report a synergistic silver-mediated and palladium-catalyzed non-directed C-H olefination of arenes with vinyl(pseudo)halides, which offers a complementary strategy to the typical Fujiwara-Moritani reaction. The reactions proceeded well for a variety of halogenated arenes, heteroarenes, and olefin substrates, providing an efficient access to various multi-substituted aryl olefins, including trisubstituted/tetrasubstituted olefins and several complex olefins derived from medicines or natural products. Mechanistic studies indicated a bimetallic Pd/Ag cooperation is operative in the catalysis, i.e., the reaction is initiated by aryl C-H bond cleavage via ligation with phosphine/Ag species, followed by transferring of the aryl moiety to a vinyl palladium intermediate,which is in turn formed by oxidative addition of vinyl(pseudo)halide to a Pd complex. This method enables the synthesis of a wide range of challenging multi-substituted vinyl products from simple arenes(directing-group free) in a streamlined and controllable fashion.

关键词： direct C–H olefination multi-substituted aryl alkenes bimetallic Pd/Ag cooperation C–H functionalization

Solubility determination and comparison ofβ-HMX and RDX in two binary mixed solvents(acetonitrile+water,nitric acid+water)

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Chinese Journal of Chemical Engineering 2024年第5期69卷 238-249页

作者： yuehua yao Fan wang Yinguang Xu Zishuai Xu Lizhen Chen Jianlong wang School of Chemistry and Chemical Engineering North University of ChinaTaiyuan 030051China Gansu Yinguang Chemical Industry Group Co.Ltd. Baiyin 730900China

In order to remove hexahydro-1,3,5-trinitro-1,3,5-triazine(RDX),the main impurity,in process of polymorphic transformation of octrahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine(HMX),the solubility ofβ-HMX and RDX in acetonitrile(ACN)+water in the temperature range of 288.15-333.15 K and in nitric acid(HNO_(3))+water in the temperature range of 298.15-333.15 K were measured by laser dynamic *** results showed that the solubility of bothβ-HMX and RDX in binary mixed solvents increased monotonously as the temperature increase at a given solvent composition or with increasing of mole fraction of solvent(ACN and nitric acid).Solubility data were well correlated by the modified Apelblat equation,Jouyban-Acree model,Yaws equation and van't Hoff equation,and the Yaws equation achieved the best fitting results according to the relative error and the mean square error ***,the solubility ofβ-HMX and RDX in binary mixed solvent was compared,based on the solubility difference and the solvent's own properties,the best separation degree ofβ-HMX and RDX was found when the mole fraction of nitric acid was 0.22 at room temperature,which provided data support for HMX crystallization in mixed *** solubility differences between RDX andβ-HMX in mixed solvents were explained from the formation of intermolecular and intramolecular hydrogen bonds.

关键词： Solubility Octrahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine Hexahydro-1,3,5-trinitro-1,3,5-triazine Separation Model Hydrogen bond

Development and evaluation of an online monitoring single-particle optical particle counter with polarization detection

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Journal of Environmental Sciences 2024年第4期138卷 585-596页

作者： Weijie yao Xiaole Pan yu Tian Hang Liu yuting Zhang Shandong Lei Junbo Zhang Yinzhou Zhang LinWu Yele Sun Zifa wang State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Center for Excellence in Regional Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China

We developed a single-particle optical particle counter with polarization detection(SOPC)for the real-time measurement of the optical size and depolarization ratio(defined as the ratio of the vertical component to the parallel component of backward scattering)of atmospheric particles,the polarization ratio(DR)value can reflect the irregularity of the *** SOPC can detect aerosol particles with size larger than 500 nm and the maximum particle count rate reaches~1.8×10^(5)particles per *** SOPC uses a modulated polarization laser to measure the optical size of particles according to forward scattering signal and the DR value of the particles by backward S and P signal *** sampling rate of the SOPC was 106#/(sec·channel),and all the raw data were processed *** calibration curve was obtained by polystyrene latex spheres with sizes of 0.5-10μm,and the average relative deviation of measurement was 3.96% for sub 3μm particles.T-matrix method calculations showed that the DR value of backscatter light at 120°could describe the variations in the aspect ratio of particles in the above size *** performed insitu observations for the evaluation of the SOPC,the mass concentration constructed by the SOPC showed good agreement with the PM_(2.5)measurements in a nearby state-controlled monitoring *** instrument could provide useful data for source appointment and regulations against air pollution.

关键词： Instrument development Single particle detection Measurement uncertainty Optical simulation Mass concentration

Synthesis of betanin by expression of the core betalain biosynthetic pathway in carrot

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Horticultural Plant Journal 2024年第3期10卷 732-742页

作者： Bo wang Yahui wang yuanjie Deng Quanhong yao Aisheng Xiong State Key Laboratory of Crop Genetics and Germplasm Enhancement College of HorticultureNanjing Agricultural UniversityNanjingJiangsu 210095China Shanghai Key Laboratory of Agricultural Genetics and Breeding Biotechnology Research Institute of Shanghai Academy of Agricultural ScienceShanghai 201106China

Betalain has received increased attention because of its high nutritional value and crucial physiological *** on the elucidation of its core biosynthetic pathway,betalain can be produced in additional plants by metabolic *** of betalain in carrot(Daucus carota L.)can improve its nutritional quality and economic value by extracting betalain from the fleshy root,non-edible part,and processing residue of *** this study,two different constructs,namely,pYB:mCD(AomelOS,BvCYP76AD1S,and BvDODA1S)and p YB:CDD(BvCYP76AD1S,BvDODA1S,and MjcDOPA5GTS),were introduced into carrot for betanin synthesis by Agrobacterium-mediated *** can be synthetized in both transgenic calli,and p YB:m CD-transgenic callus can be used to produce betacyanin by suspension ***,pYB:mCD-transgenic seedlings can synthetize betanin only by tyrosine *** p YB:CDD-transgenic lines can synthetize betanin in whole *** betanin content in fleshy root of pYB:CDD-transgenic carrot was(63.4±9)μg·g^(-1)fresh weight according to quantitative *** betanin-producing carrot plant materials can be used to synthesize betanin for industrial application or consumption as dietary sources.

关键词： Daucus carota L. Betanin Biosynthesis Metabolic engineering Biofortification

Efficient hydrogenolysis of fructose to 1,2-propanediol over bifunctional Ru-WO_(x)-MgO_(y) catalysts under mild reaction conditions via enhancing the chemoselective cleavage of C-C bonds

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Journal of Energy Chemistry 2024年第5期92卷 311-321页

作者： Shuang Luo Tie Shu Min Mao Haijie yu yuxin Zheng Daqian Ding Lingmei Liu Kexin yao Jianjian wang School of Chemistry and Chemical Engineering State Key Laboratory of Coal Mine Disaster Dynamics and ControlInstitute of Advanced Interdisciplinary StudiesMulti-scale Porous Materials CenterChongqing UniversityChongqing 401331China Key Laboratory for Efficient Conversion and Circular Economy of Coal Chemical Engineering CollegeInner Mongolia University of TechnologyHohhot 010051Inner MongoliaChina

Selective conversion of fructose to 1,2-propanediol(1,2-PDO)is considered as a sustainable and cost-effective alternative to petroleum-based processes,however,this approach still faces challenges associated with low efficiency and harsh reaction ***,we have successfully synthesized a novel bifunctional Ru-WO_(x)-MgO_(y) catalyst through a facile'one-pot'solvothermal ***,this catalyst exhibits exceptional catalytic performances in the conversion of fructose to 1,2-PDO under mild reaction *** yield of 1,2-PDO is up to 56.2%at 140°C for 4 h under an ultra-low hydrogen pressure of only 0.2 MPa,surpassing the reported results in recent literature(below 51%).Comprehensive characterizations and density functional theory(DFT)calculations reveal that the presence of oxygen vacancies in the Ru-WO_(x)-MgO_(y) catalyst,serving as active acidic sites,facilitates the chemoselective cleavage of C-C bonds in fructose,which leads to the generation of active intermediates and ultimately resulted in the high yield of 1,2-PDO.

关键词： Biomass Fructose 1,2-Propanediol Retroaldol condensation Heterogenous catalysis