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Triple three-dimensional MS/MS spectrum facilitates quantitative ginsenosides-targeted sub-metabolome characterization in notoginseng

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Acta Pharmaceutica Sinica B 2024年第9期14卷 4045-4058页

作者： Ke Zhang Jinru Jia Ting Li Wenjing Liu Pengfei tu jian-Bo Wan jun Li Yuelin Song Modern Research Center for Traditional Chinese Medicine Beijing Research Institute of Chinese MedicineBeijing University of Chinese MedicineBeijing 100029China SCIEX china Beijing 100015China school of Pharmacy Henan University of Chinese MedicineZhengzhou 450046China State Key Laboratory of Quality Research in Chinese Medicine Institute of Chinese Medical SciencesUniversity of MacaoTaip1Macao 999078China

Although serving as the workhorse,MS/MS cannot fully satisfy the analytical requirements of quantitative sub-metabolome *** more information intrinsically correlates to more structural and concentration clues,here,efforts were devoted to comprehensively tracing and deciphering MS/MS behaviors through constructing triple three-dimensional(33D)-MS/MS ***-targeted metabolomics of notoginseng,one of the most famous edible medicinal plants,was employed as a *** authentic ginsenosides were deployed to build the correlations between 33D-MS/MS spectra and structure/concentration *** assaying ginsenosides with progressive concentrations using QTOF-MS to configure 1st 3D spectrum,the generations of MS1 spectral signals,particularly multi-charged multimer anions,e.g.,[2Me2H]2e and[2Mt2HCOO]2e ions,relied on both concentration and the amount of sugar *** programming progressive collision energies to the front collision cell of Qtrap-MS device to gain 2nd 3D spectrum,optimal collision energy(OCE)corresponding to the glycosidic bond fission was primarily correlated with the masses of precursor and fragment ions and partially governed by the glycosidation *** quantitative relationships between OCEs and masses of precursor and fragment ions were utilized to build large-scale quantitative program for *** applying progressive exciting energies to the back collision chamber to build 3rd 3D spectrum,the fragment ion and the decomposition product anion exhibited identical dissociation trajectories when they shared the same molecular *** ginsenosides-focused quantitative metabolomics,significant differences occurred for sub-metabolome amongst different parts of *** differential ginsenosides were confirmatively identified by applying the correlations between 33D-MS/MS spectra and ***,33D-MS/MS spectrum covers all MS/MS behaviors and dramatically faci

关键词： Quantitative submetabolome characterization Ginsenosides Structural identification Notoginseng Full exciting energy ramp-MS3 spectrum

Influence of pore structure heterogeneity on channeling channels during hot water flooding in heavy oil reservoir based on CT scanning

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Petroleum science 2024年第4期21卷 2407-2419页

作者： Qing-jun Du Hao-Yu Zheng jian Hou Yong-Ge Liu jian-Fang Sun Dong Zhao State Key Laboratory of Deep Oil and Gas China University of Petroleum (East China) school of Petroleum Engineering China University of Petroleum (East China) Laboratory for Marine Mineral resources Qingdao National Laboratory for Marine Science and Technology Petroleum Exploration and Production Research Institute

Hot water flooding is an effective way to develop heavy oil reservoirs. However, local channeling channels may form, possibly leading to a low thermal utilization efficiency and high water cut in the reservoir. The pore structure heterogeneity is an important factor in forming these channels. This study proposes a method that mixes quartz sand with different particle sizes to prepare weakly heterogeneous and strongly heterogeneous models through which hot water flooding experiments are *** the experiments, computer tomography(CT) scanning identifies the pore structure and micro remaining oil saturation distribution to analyze the influence of the pore structure heterogeneity on the channeling channels. The oil saturation reduction and average pore size are divided into three levels to quantitatively describe the relationship between the channeling channel distribution and pore structure heterogeneity. The zone where oil saturation reduction exceeds 20% is defined as a channeling *** scanning area is divided into 180 equally sized zones based on the CT scanning images, and threedimensional(3D) distributions of the channeling channels are developed. Four micro remaining oil distribution patterns are proposed, and the morphology characteristics of micro remaining oil inside and outside the channeling channels are analyzed. The results show that hot water flooding is more balanced in the weakly heterogeneous model, and the oil saturation decreases by more than 20% in most zones without narrow channeling channels forming. In the strongly heterogeneous model, hot water flooding is unbalanced, and three narrow channeling channels of different lengths form. In the weakly heterogeneous model, the oil saturation reduction is greater in zones with larger pores. The distribution range of the average pore size is larger in the strongly heterogeneous model. The network remaining oil inside the channeling channels is less than outside the channeling channels,

关键词： Heavy oil Hot water flooding Pore structure Channeling channels CT scanning

UDT:U-shaped deformable transformer for subarachnoid haemorrhage image segmentation

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CAAI Transactions on Intelligence Technology 2024年第3期9卷 756-768页

作者： Wei Xie Lianghao Jin Shiqi Hua Hao Sun Bo Sun Zhigang tu jun Liu Hubei Provincial Key Laboratory of Artificial Intelligence and Smart Learning Central China Normal UniversityWuhanChina school of Computer science Central China Normal UniversityWuhanChina National Language resources Monitoring and Research Center for Network Media Central China Normal UniversityWuhanChina The First Affiliated Hospital of Dalian Medical university DalianChina State Key Laboratory of Information Engineering in Surveying Mapping and Remote SensingWuhan UniversityWuhanChina Information Systems Technology and Design Pillar Singapore University of Technology and DesignSingaporeSingapore

Subarachnoid haemorrhage(SAH),mostly caused by the rupture of intracranial aneu-rysm,is a common disease with a high fatality *** lesions are generally diffusely distributed,showing a variety of scales with irregular *** complex characteristics of lesions make SAH segmentation a challenging *** cope with these difficulties,a u-shaped deformable transformer(UDT)is proposed for SAH ***,first,a multi-scale deformable attention(MSDA)module is exploited to model the diffuseness and scale-variant characteristics of SAH lesions,where the MSDA module can fuse features in different scales and adjust the attention field of each element dynamically to generate discriminative multi-scale ***,the cross deformable attention-based skip connection(CDASC)module is designed to model the irregular edge char-acteristic of SAH lesions,where the CDASC module can utilise the spatial details from encoder features to refine the spatial information of decoder ***,the MSDA and CDASC modules are embedded into the backbone Res-UNet to construct the proposed *** experiments are conducted on the self-built SAH-CT dataset and two public medical datasets(GlaS and MoNuSeg).Experimental results show that the presented UDT achieves the state-of-the-art performance.

关键词： image segmentation medical image processing

Intelligent geochemical interpretation of mass chromatograms:Based on convolution neural network

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Petroleum science 2024年第2期21卷 752-764页

作者： Kai-Ming Su jun-Gang Lu jian Yu Zi-Xing Lu Shi-Jia Chen Hubei Key Laboratory of Petroleum Geochemistry and environment Wuhan430100HubeiChina College of resources and environment Yangtze UniversityWuhan430100HubeiChina school of Geoscience and Technology Southwest Petroleum UniversityChengdu610500SichuanChina Changqing Oilfield Company PetroChinaXi'an710021ShaanxiChina

Gas chromatography-mass spectrometry(GC-MS)is an extremely important analytical technique that is widely used in organic *** is the only approach to capture biomarker features of organic matter and provides the key evidence for oil-source correlation and thermal maturity ***,the conventional way of processing and interpreting the mass chromatogram is both timeconsuming and labor-intensive,which increases the research cost and restrains extensive applications of this *** overcome this limitation,a correlation model is developed based on the convolution neural network(CNN)to link the mass chromatogram and biomarker features of samples from the Triassic Yanchang Formation,Ordos Basin,*** this way,the mass chromatogram can be automatically *** research first performs dimensionality reduction for 15 biomarker parameters via the factor analysis and then quantifies the biomarker features using two indexes(*** and PMI)that represent the organic matter thermal maturity and parent material type,***,training,interpretation,and validation are performed multiple times using different CNN models to optimize the model structure and hyper-parameter setting,with the mass chromatogram used as the input and the obtained MI and PMI values for supervision(label).The optimized model presents high accuracy in automatically interpreting the mass chromatogram,with R2values typically above 0.85 and0.80 for the thermal maturity and parent material interpretation results,*** significance of this research is twofold:(i)developing an efficient technique for geochemical research;(ii)more importantly,demonstrating the potential of artificial intelligence in organic geochemistry and providing vital references for future related studies.

关键词： Organic geochemistry Biomarker Mass chromatographic analysis Automated interpretation Convolution neural network Machine learning

Influence of cutterhead opening ratio on soil arching effect and face stability during tunnelling through non-uniform soils

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Underground Space 2024年第4期17卷 45-59页

作者： Xue-jian Chen Pei-Pei Fang Qiu-Nan Chen jun Hu Kai Yao Yong Liu State Key Laboratory of Water resources Engineering and Management Wuhan UniversityWuhan 430072China Hubei Technology Innovation Center for Smart Hydropower Wuhan 430000China College of Civil Engineering Anhui Jianzhu UniversityHefei 230601China school of Civil Engineering Hunan University of Science and TechnologyXiangtan 411201China school of Civil and Architectural Engineering Hainan UniversityHaikou 570228China school of Qilu Transportation Shandong UniversityJinan 250002China

tunnelling has increasingly become an essential tool in the exploration of underground space.A typical construction problem is the face instability during tunnelling,posing a great threat to associated *** face instability often occurs with the soil arching *** study investigates the combined effect of cutterhead opening ratio and soil non-uniformity on soil arching effect and face stability,via conducting random finite-element analysis coupled with Monte–Carlo *** results underscore that the face stability is strongly associated with the evolution of stress *** obtained stability factors in the uniform soils can serve as a reference for the design of support pressure in practical tunnelling *** addition,non-uniform soils exhibit a lower stability factor than uniform soils,which implies that the latter likely yields an underestimated probability of face *** tunnel face is found to have a probability of failure more than 50%if the spatial non-uniformity of soil is *** the end,a practical framework is established to determine factor of safety(FOS)corresponding to different levels of probability of face failure considering various opening ratios in non-uniform *** required FOS is 1.70 to limit the probability of face instability no more than 0.1%.Our findings can facilitate the prediction of probability of instability in the conventionally deterministic design of face pressure.

关键词： tunnel Face stability Soil arching effect Cutterhead opening ratio Non-uniform soil Random field

Rapid lithium-ion insertion/extraction and migration behavior of Na_(2)WO_(4)-encapsulated lithium-rich layered oxide cathode

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Rare Metals 2024年第8期43卷 3647-3660页

作者： Yu-Shen Zhao Fan-Fan Wang jian-Cang Wang Peng-Fei Wang Ting-Feng Yi jun-Hong Zhang school of Materials science and Engineering Northeastern UniversityShenyangShenyang 110819China Key Laboratory of Dielectric and Electrolyte Functional Material Hebei Province School of Resources and MaterialsNortheastern University at QinhuangdaoQinhuangdao 066004China Shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell Technology College of Chemistry and Chemical EngineeringLiaocheng UniversityLiaocheng 252059China

Due to the low cost,high working voltage and high storage capacity,Li-rich Mn-based layered compounds show promise as the cathode materials for lithiumion batteries(LIBs).However,the side reactions at the solid-liquid interface of the cathode will lead to rapid capacity decay and inferior rate ***,this article proposes a liquid-phase dispersion strategy to introduce a Na_(2)WO_(4)layer on the Li_(1.2)Ni_(0.13)-Co_(0.13)Mn_(0.54)O_(2) cathode,which can reduce the side effects between raw materials and electrolyte and promote the insertion/extraction rate of Li^(+),thus enhancing the material stability and rate *** a result,the capacity retention rate is 96.9%after 200 cycles under ***,the capacities are 177.5,149.5,111.1 and58.3 mAh·g^(-1)at 1C,2C,5C and 10C,implying a superior fast charging *** exceptional performance can be ascribed to both the increased conductivity and enhanced structural stability of the cathode ***'s more,based on the investigation of ion insertion/extraction behavior in electrode materials and the ion migration kinetics in the electrolyte,this study suggests that coating Li-rich Mn-based materials with Na_(2)WO_(4)can be a promising strategy to improve their performance in LIBs.

关键词： Li-ion battery Coating Rate performance Li_(1.2)Ni_(0.13)Co_(0.13)Mn_(0.54)O_(2) Reaction kinetics

Recent advancements in hydrometallurgical recycling technologies of spent lithium-ion battery cathode materials

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Rare Metals 2024年第3期43卷 879-899页

作者： Juan Wu Li Xiao Li Shen jian-jun Ran Hui Zhong Yi-Rong Zhu Han Chen College of Materials and Advanced Manufacturing Hunan University of TechnologyZhuzhou412007China school of resources Processing and Bioengineering Central South UniversityChangsha410083China Guangdong jiana Energy Technology Company Qingyuan513000China

The rapidly increasing production of lithium-ion batteries(LIBs)and their limited service time increases the number of spent LIBs,eventually causing serious environmental issues and resource *** the perspectives of clean production and the development of the LIB industry,the effective recovery and recycling of spent LIBs require urgent *** study provides an overview of the current hydrometallurgical processes employed in the recycling of spent cathode materials,focusing on the leaching of valuable metals and their *** particular,this research reviews the various leaching systems(inorganic acid,organic acid,and ammonia)and the separation of valuable metals,and then,recommendations for subsequent study are offered in an attempt to contribute to the development of highly efficient methods for recycling spent cathode *** addition,a range of existing technologies,such as solvent extraction,chemical precipitation,electrochemical deposition,and regeneration,for the postprocessing of leaching solutions are ***,the promising technologies,existing challenges and suggestions with respect to the development of effective and environmentally friendly recycling methods for handling spent cathode materials are identified.

关键词： Spent lithium-ion batteries(LIBs) Cathode material Hydrometallurgy Leaching Recycling

High-timing-precision detection of single X-ray photons by superconducting nanowires

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National science Review 2024年第1期11卷 194-203页

作者： Shuya Guo Jingrou Tan Hengbin Zhang Jinguang Wang Tianhao Ji Labao Zhang Xiaolong Hu jian Chen jun Xie Kai Zou Yun Meng Xiaomin Bei Ling-An Wu Qi Chen Hao Wang Xuecou tu Xiaoqing Jia Qing-Yuan Zhao Lin Kang Peiheng Wu Research Institute of Superconductor Electronics Nanjing University Qian Xuesen Laboratory of Space Technology Beijing National Laboratory of Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Hefei National Laboratory school of Precision Instrument and Optoelectronic Engineering Tianjin University Key Laboratory of Optoelectronic Information science and Technology Ministry of Education

Precisely acquiring the timing information of individual X-ray photons is important in both fundamental research and practical applications. The timing precision of commonly used X-ray single-photon detectors remains in the range of one hundred picoseconds to microseconds. In this work, we report on high-timing-precision detection of single X-ray photons through the fast transition to the normal state from the superconductive state of superconducting nanowires. We successfully demonstrate a free-running X-ray single-photon detector with a timing resolution of 20.1 ps made of 100-nm-thick niobium nitride film with an active area of 50 μm by 50 μm. By using a repeated differential timing measurement on two adjacent X-ray single-photon detectors, we demonstrate a precision of 0.87 ps in the arrival-time difference of X-ray photon measurements. Therefore, our work significantly enhances the timing precision in X-ray photon counting, opening a new niche for ultrafast X-ray photonics and many associated applications.

关键词： single-photon detection timing precision superconductor ultrafast phenomenon pulsar X-ray navigation

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县级土地开发整理规划编制技术探讨

西南师范大学学报（自然科学版） 2003年第4期28卷 639-643页

作者：涂建军西南师范大学国土资源研究所重庆400715

指出土地开发整理规划方法应以实用的常规方法为主导,同时运用GIS等先进的技术手段,实现定性、定量、定位、定序的有机结合,突出规划的实用性和可操作性.

关键词：土地管理土地开发土地整理土地规划 GIS 编制方法重庆开县