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Science China Chemistry 2024年第1期67卷 368-373页

作者： Xing-Yu Wang Pei Xu Wen-Wen Liu hao-qiang Jiang Song-Lei Zhu Dong Guo Xu Zhu Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy School of PharmacyXuzhou Medical UniversityXuzhou 22100China

Unprecedented divergent synthesis of gem-difluorovinylacetic acid and glutaric acid derivatives fromα-CF_(3)alkenes with formate as the carbonyl source was *** reaction can undergo selective mono-or triple C-F bond cleavage by simply switching the photocatalyst and hydrogen atom transfer(HAT)catalyst under visible-light-induced conditions at room *** acts as both the C1 source and the reductant through the generation of CO_(2)^(·-)species,which underwent Giese radical addition to electron-deficient alkenes to trigger the consecutive C-F bond cleavage and carboxylation process.

关键词： C-F bond activation defluorocarboxylation carbon dioxide radical anion visible light

A compact X-band backward traveling-wave accelerating structure

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Nuclear Science and Techniques 2024年第5期35卷 13-29页

作者： Xian-Cai Lin hao Zha Jia-Ru Shi qiang Gao Fang-Jun Hu Qing-Zhu Li Huai-Bi Chen Department of Engineering Physics Tsinghua UniversityBeijing 100084China Key Laboratory of Particle and Radiation Imaging(Tsinghua University) Ministry of EducationBeijing 100084China

Very high-energy electrons(VHEEs)are potential candidates for FLASH radiotherapy for deep-seated *** proposed a compact VHEE facility based on an X-band high-gradient high-power *** this study,we investigated and realized the first X-band backward traveling-wave(BTW)accelerating structure as the buncher for a VHEE facility.A method for calculating the parameters of single cell from the field distribution was introduced to simplify the design of the BTW ***-domain circuit equations were applied to calculate the transient beam parameters of the buncher in the unsteady state.A prototype of the BTW structure with a thermionic cathode-diode electron gun was designed,fabricated,and tested at high power at the Tsinghua X-band high-power test *** structure successfully operated with 5-MW microwave pulses from the pulse compressor and outputted electron bunches with an energy of 8 MeV and a pulsed current of 108 mA.

关键词： backward traveling-wave accelerating structure Equivalent circuit model High-power test Very high-energy electron radiotherapy

Efficient second and third harmonic generation in dual-layer lithium niobate microdisk resonator

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Science China(Physics,Mechanics & Astronomy) 2024年第5期67卷 33-38页

作者： Zhenzhong hao Xiao Wu qiang Luo Zhang Li Rui Ma Fang Bo Feng Gao Guoquan Zhang Jingjun Xu MOE Key Laboratory of Weak-Light Nonlinear Photonics TEDA Institute of Applied Physics and School of PhysicsNankai UniversityTianjin 300457China

Lithium niobate thin film frequency doubler has extensive applications in the preparation of classical and quantum *** this study,we successfully fabricated microdisk resonators with a quality factor of 2.2×10^(5) in reverse-polarization dual-layer x-cut lithium niobate for the first *** on the modal phase matching condition,efficient second harmonic generation with a record normalized conversion efficiency of~56000%W-1 and cascaded third harmonic generation with an efficiency of~6500%W-2 were obtained in the microdisk *** with the periodically poled lithium niobate microcavity,the complex domain structure preparation processes are *** work provides a scheme for achieving highly efficient second-order nonlinear effects in non-periodically poled microcavities.

关键词： harmonic lithium niobate

Selective photocatalytic oxidation of methane to C1 oxygenates by regulating sizes and facets over Au/ZnO

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Nano Research 2024年第5期17卷 3810-3818页

作者： qiang Zhou Xinyu Wang Xiaojie Tan Qinhua Zhang hao Yang Tao Xing Mingqing Wang Mingbo Wu Wenting Wu State Key Laboratory of Heavy Oil Processing College of Chemistry and Chemical Engineering&Institute of New EnergyChina University of Petroleum(East China)Qingdao 266580China National Engineering Research Center of Coal Gasification and Coal-based Advanced Materials ShanDong Energy Group CO.LTDJinan 250101China

Photocatalytic oxidation of methane to value-added chemicals is a promising process under mild conditions,nevertheless confronting great challenges in efficiently activating C-H bonds and inhibiting ***,we propose a comprehensive strategy for the selective generation of reactive oxygen species(ROS)by regulating the sizes and facets of Au nanoparticles loaded on *** photocatalytic methane oxidation at ambient temperature,a high oxygenates yield of 36.4 mmol·g^(-1)·h^(-1) with a nearly 100%selectivity has been achieved over the optimized 1.0%Au/ZnO-9.6(1%Au with(111)facet and 9.6 nm size on ZnO)photocatalyst,exceeding most reported *** investigations reveal that 1.0%Au/ZnO-9.6 with the medium size and Au(111)facet guarantees the favourable formation of superoxide radicals(·OOH)through mild oxygen reduction,ultimately leading to excellent photocatalytic methane oxidation *** work provides some guidance for the delicate design of photocatalysts for efficient photocatalytic methane oxidation and oxygen utilization.

关键词： photocatalysis methane oxidation radical regulation oxygen activation nanomaterial

Aboveground biomass stocks of species-rich natural forests in southern China are influenced by stand structural attributes,species richness and precipitation

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Plant Diversity 2024年第4期46卷 530-536页

作者： Wen-hao Zeng Shi-Dan Zhu Ying-Hua Luo Wei Shi Yong-qiang Wang Kun-Fang Cao State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources College of ForestryGuangxi UniversityNanning 530004China Guangxi Key Laboratory of Forest Ecology and Conservation College of ForestryGuangxi UniversityNanning 530004China Key Laboratory of National Forestry and Grassland Administration on Biodiversity Conservation in Karst Mountainous Areas of Southwestern China School of Life SciencesGuizhou Normal UniversityHuaxi College TownGui'an DistrictGuiyang 550025China

Forests,the largest terrestrial carbon sinks,play an important role in carbon sequestration and climate change *** forest attributes and environmental factors have been shown to impact aboveground biomass,their influence on biomass stocks in species-rich forests in southern China,a biodiversity hotspot,has rarely been *** this study,we characterized the effects of environmental factors,forest structure,and species diversity on aboveground biomass stocks of 30 plots(1 ha each) in natural forests located within seven nature reserves distributed across subtropical and marginal tropical zones in Guangxi,*** results indicate that forest aboveground biomass stocks in this region are lower than those in mature tropical and subtropical forests in other ***,we found that aboveground biomass was positively correlated with stand age,mean annual precipitation,elevation,structural attributes and species richness,although not with species *** we compared stands with the same basal area,we found that aboveground biomass stock was higher in communities with a higher coefficient of variation of diameter at breast *** findings highlight the importance of maintaining forest structural diversity and species richness to promote aboveground biomass accumulation and reveal the potential impacts of precipitation changes resulting from climate warming on the ecosystem services of subtropical and northern tropical forests in ***,many natural forests in southern China are not fully ***,their continued growth will increase their carbon storage over time.

关键词： Subtropical forest Marginal tropical forest Aboveground biomass Species diversity Forest structural attribute Environment factor

Dcalycinumines A-E,Alkaloids with Cytotoxic Activities of Nasopharyngeal Carcinoma Cells from Daphniphyllum calycinum

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Chinese Journal of Chemistry 2024年第1期42卷 35-42页

作者： Qing Tang Xiao-Yong Dai qiang Lin Zhi-Peng Ling Yi-Kun hao Tian-Xi Zhu Ji-Hui Zhang Yi-Bo Hou Yao-Lan Li Lai-qiang Huang Jing-hao Wang Guo-Cai Wang Yu-Bo Zhang Guangdong Clinical Translational Centerfor Targeted Drug Department of PharmacologySchoolof MedicineJinan University GuangzhouGuangdong 510632China Institute of Traditional Chinese Medicine&Natural Products Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and New Drugs ResearchCollegeof PharmacyJinan UniversityGuangzhouGuangdong511443China Institute of Biopharmaceutical and Health Engineering Shenzhen Key Laboratory of Gene and Antibody TherapyState Key Laboratory of Chemical OncogenomicsShenzhen International Graduate SchoolTsinghua UniversityShenzhenGuangdong 518055China The Guangzhou Key Laboratoryof basic and Translational Research on Chronic Disease Department of PharmacyThe First Affiliated HospitalJinan UniversityGuangzhouGuangdong 510630China

Fivenovel Daphniphyllum alkaloids,named dcalycinumines A-E(1-4,6),andeight previously described Daphniphyllum alkaloids(5,7-13)were isolated from Daphniphyllum *** 1 is the first Daphniphyllum alkaloid possessing a highly rearranged 6/6/6/7/5/6 hexacyclic architecture with a unique 3-methyl-1-azabicyclo[4,4,0]decane ring *** 2 represents a rare diamino Daphniphyllum alkaloid with an unprecedented 6/5/5/6/6/5 carbon skeleton featuring a unique 1-aza-6-azaspiro[4,5]decane unit,whereas 3 also represents a rare diamino Daphniphyllum alkaloid as a possible precursor of *** 4 is the second example of c-22-nor yuzurimine-type *** structures and absolute configurations were elucidated by HRESIMS,NMR spectroscopic analyses,EcD calculations,and single-crystal X-ray ***,compound 1 showed remarkable antitumor activities,which could inhibit the proliferation,migration and invasion of nasopharyngeal carcinoma cells,and promoted nasopharyngeal carcinoma cells apoptosis.

关键词： Daphniphyllum calycinum Natural products Daphniphyllum alkaloid Structural elucidation Biological activity Apoptosis Nasopharyngealcarcinoma

Hydrocarbon gas huff-n-puff optimization of multiple horizontal wells with complex fracture networks in the M unconventional reservoir

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Petroleum Science 2024年第2期21卷 1018-1031页

作者： hao-Chuan Zhang Yong Tang You-Wei He Yong Qin Jian-Hong Luo Yu Sun Ning Wang De-qiang Wang State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu610500SichuanChina CNPC Research Institute of Petroleum Exploration&Development Beijing100083China Southwest Oil&Gas Field Company PetroChinaChengdu610051SichuanChina State Key Laboratory of Offshore Oil Exploitation CNOOC Research Institute Co.LtdBeijing100027China

The oil production of the multi-fractured horizontal wells(MFHWs) declines quickly in unconventional oil reservoirs due to the fast depletion of natural energy. Gas injection has been acknowledged as an effective method to improve oil recovery factor from unconventional oil reservoirs. Hydrocarbon gas huff-n-puff becomes preferable when the CO_(2) source is limited. However, the impact of complex fracture networks and well interference on the EOR performance of multiple MFHWs is still unclear. The optimal gas huff-n-puff parameters are significant for enhancing oil recovery. This work aims to optimize the hydrocarbon gas injection and production parameters for multiple MFHWs with complex fracture networks in unconventional oil reservoirs. Firstly, the numerical model based on unstructured grids is developed to characterize the complex fracture networks and capture the dynamic fracture ***, the PVT phase behavior simulation was carried out to provide the fluid model for numerical simulation. Thirdly, the optimal parameters for hydrocarbon gas huff-n-puff were obtained. Finally, the dominant factors of hydrocarbon gas huff-n-puff under complex fracture networks are obtained by fuzzy mathematical method. Results reveal that the current pressure of hydrocarbon gas injection can achieve miscible displacement. The optimal injection and production parameters are obtained by single-factor analysis to analyze the effect of individual parameter. Gas injection time is the dominant factor of hydrocarbon gas huff-n-puff in unconventional oil reservoirs with complex fracture networks. This work can offer engineers guidance for hydrocarbon gas huff-n-puff of multiple MFHWs considering the complex fracture networks.

关键词： Unconventional oil reservoir Complex fracture network Hydrocarbon gas huff-n-puff Parameter optimization Numerical simulation

Verteporfin fluorescence in antineoplastic-treated pancreatic cancer cells found concentrated in mitochondria

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World Journal of Gastrointestinal Oncology 2024年第3期16卷 968-978页

作者： Ying-Qiao Zhang Qing-hao Liu Lu Liu Peng-Yu Guo Run-Ze Wang Zhi-Chang ba Department of Radiology Harbin Medical University Cancer HospitalHarbin 150010Heilongjiang ProvinceChina Department of Digestive Internal Medicine Harbin Medical University Cancer HospitalHarbin 150010Heilongjiang ProvinceChina

baCKGROUND Traditional treatments for pancreatic cancer(PC)are *** therapy(PDT)is non-invasive,and proven safe to kill cancer cells,including ***,the mitochondrial concentration of the photosensitizer,such as verteporfin,is *** To investigate the distribution of fluorescence of verteporfin in PC cells treated with antitumor drugs,*** Workable survival rates of PC cells(AsPC-1,BxPC-3)were determined with chemotherapy[doxorubicin(DOX)and gemcitabine(GEM)]and non-chemotherapy[sirolimus(SRL)and cetuximab(CTX)]drugs in vitro,with or without verteporfin,as measured via MTT,flow cytometry,and laser confocal *** cell proliferation was associated with GEM that was more enduring compared with *** laser microscopy allowed observation of GEM-and verteporfin-treated PC cells co-stained with 4’,6-diamidino-2-phenylindole and MitoTracker Green to differentiate living and dead cells and subcellular localization of verteporfin,*** Cell survival significantly dropped upon exposure to either chemotherapy drug,but not to SRL or *** cell lines responded similarly to *** intensity of fluorescence was associated with the concentration of *** experiments using GEM showed that survival rates of the PC cells treated with 10μmol/L verteporfin(but not less)were significantly lower relative to nil *** and dead stained cells treated with GEM were *** GEM treatment,verteporfin was observed primarily in the *** Verteporfin was observed in living *** GEM-treated human PC cells,verteporfin was particularly prevalent in the *** study supports further study of PDT for the treatment of PC after neoadjuvant chemotherapy.

关键词： Photodynamic therapy Pancreatic cancer Verteporfin Mitochondria Chemotherapy Gemcitabine

Chromosome-level assembly of triploid genome of Sichuan pepper(Zanthoxylum armatum)

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Horticultural Plant Journal 2024年第2期10卷 437-449页

作者： Lizhi Song Yue Huang hao Zuo Ning Tang Zhengguo Li Wenbiao Jiao Feng Xu qiang Xu Zexiong Chen National Key Laboratory for Germplasm Innovation and Utilization for Fruit and Vegetable Horticultural Crops Huazhong Agricultural UniversityWuhanHubei 430070China Chongqing Key Laboratory of Economic Plant Biotechnology Chongqing University of Arts and SciencesChongqing 402160China School of Life Sciences Chongqing UniversityChongqing 400030China College of Horticulture and Gardening Yangtze UniversityJingzhouHubei 434025China College of Informatics Huazhong Agricultural UniversityWuhanHubei 430070China

As an important spice species in Rutaceae, the Sichuan pepper (Zanthoxylum armatum) can provide pungent and numbing taste, as well as aroma in its mature fruit. Here we assembled a chromosome-level genome of green prickly ash which was widely cultivated in a major production area including Chongqing and Sichuan province, China. We generated 712 Gb (~112×) PacBio long reads and 511 Gb (~82×) Hi-C data, and yielded an assembly of 99 pseudochromosomes with total size of 5.32 Gb and contig N50 of 796 kb. The genomic analyses and cytogenetic experiments both indicated that the cultivarZhuye Huajiao’ was a triploid. We identified a Zanthoxylum-specific whole genome duplication event emerging about 24.8 million years ago (Mya). We also detected a transposition burst event (0.3-0.4 Mya) responsible for the large genome size of Z. armatum. Metabolomic analysis of the Zanthoxylum fruits during development stages revealed profiles of39 volatile aroma compounds and 528 secondary metabolites, from which six types of sanshools were identified. based on metabolomic and transcriptomic network analysis, we screened candidate genes encoding long chain acyl-CoA synthetase, fatty acid desaturase,branched-chain amino acid aminotransferase involved in sanshool biosynthesis and three genes encoding terpene synthase during fruit development. The multi-omics data provide insights into the evolution of Zanthoxylum and molecular basis of numbing and aroma flavor of Sichuan pepper.

关键词： Zanthoxylum armatum Genome Sanshool Terpenoid

Dynamic mechanical characteristics of deep Jinping marble in complex stress environments

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第2期16卷 630-644页

作者： Chendi Lou Heping Xie Ru Zhang Hai Ren hao Luo Kun Xiao Yuan Peng qiang Tan Li Ren Institute for Disaster Management and Reconstruction Sichuan UniversityChengdu610207China College of Water Resource&Hydropower Sichuan UniversityChengdu610065China MOE Key Laboratory of Deep Earth Science&Engineering Sichuan UniversityChengdu610065China Yalong River Hydropower Development Company Ltd.Chengdu610051China (Chongqing)International Engineering Technology Company Ltd.Chongqing401121China

To reveal the dynamic mechanical characteristics of deep rocks,a series of impact tests under triaxial static stress states corresponding to depths of 300-2400 m were *** results showed that both the strain rates and the stress environments in depth significantly affect the mechanical characteristics of *** sensitivity of strain rate to the dynamic strength and deformation modulus shows a negative correlation with depth,indicating that producing penetrative cracks in deep environments is more difficult when damage *** dynamic strength shows a tendency to decrease and then increase slightly,but decreases sharply *** demonstrates a similar trend as that of strength,whereas reflectivity indicates the opposite ***,two critical depths with high dynamically induced hazard possibilities based on the China Jinping Underground Laboratory(CJPL)were proposed for deep *** first critical depth is 600-900 m,beyond which the sensitivity of rock dynamic characteristics to the strain rate and restraint of circumferential stress decrease,causing instability of surrounding rocks under axial stress *** second one lies at 1500-1800 m,where the wave impedance and dynamic strength of deep surrounding rocks drop sharply,and the dissipation energy presents a negative *** suggests that the dynamic instability of deep surrounding rocks can be divided into dynamic load dominant and dynamic load induced types,depending on the second critical depth.

关键词： Rock mechanics Split-Hopkinson pressure bar Coupled static‒dynamic loading Different depths Holmquist-Johnson-Cook(HJC)model