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Chinese Journal of Structural Chemistry 2006年第8期25卷 937-939页

作者： SHI Jing-Min XU Hong-Kun wu chang-ju LIU Lian-Dong Department of Chemistry Shandong Normal University Jinan 250014 China

The three-dimensional complex [Cd（μ1,3-SCN）（μ3-pco）]n has been synthesized with μ1,3-SCN^- and pco as mixed bridged ligands. The crystal belongs to monoclinic, space group P21/n with a = 10.3777（16）, b = 6.2592（9）, c = 13.150（2） A, β= 97.317（2）°, V= 847.2（2） A^3, Z= 4, C6H3CdN3O3S, Mr = 309.575, Dc = 2.427 g/cm^3, F（000） = 592 and μ = 2.804 mm^-1. The structure was refined to R = 0.0255 and wR = 0.0550 for 1712 observed reflections （1 〉 2σ（I））. In the crystal the Cd（Ⅱ） ions are coordinated by μ1,3-SCN^- and μ3-pco bridge ligands to form a three-dimensional structure.

关键词： synthesis crystal structure cadmium(Ⅱ) complex thiocyanate aromatic N-oxide

Spectrofluorimetric Determination of Trace Amounts of Gallium with Salicylaldehyde Benzoylhydrazone

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Chemical Research in Chinese Universities 1998年第3期14卷 37-41页

作者： TANG Bo wu chang ju WANG Hong jian YEN Jian chong Department of Chemistry Shandong Normal UniversityJinan250014

The fluorescent reagent salicylaldehyde benzoylhydrazone(SABH) was synthesized and its ionization constants were estimated spectrophotometrically. The fluorescent reaction of this reagent with gallium was studied. Based on this chelation reaction, a spectrofluorimetric method was developed for the determination of gallium in a water medium at pH 3.2. Under these conditions, the Ga SABH complex has excitation and emission maxima at 372 and 455 nm, respectively. The linear range of the method was 0～150 μg/L and the detection limit was 0.36 μg/L of gallium when a standard addition method was used in the assay. The molar ratio of gallium to the reagent was 1∶3. The interference of other ions was studied. The extraction with n butyl acetate from a 6 mol/L hydrochloric acid medium was used to separate Ga from the interfering elements in semiconductor silicon and geological samples, and themethod has been successfully applied to the determination of gallium in these samples.

关键词： Salicylaldehyde benzoylhydrazone Gallium determination Spectrofluorimetry

Syntheses and Crystal Structures of Two Coordination Polymers with Aromatic Dioxide as Bridge Ligands

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Chinese Journal of Structural Chemistry 2007年第2期26卷 214-218页

作者： SHI Jing-Min XU Hai-Yan ZHANG Feng-Xia wu chang-ju LIU Lian-Dong Department of Chemistry Shandong Normal University Jinan 250014 China

Two coordination polymers, namely, two-dimensional complex 1 {[Cu（μ- L）1.5（ClO4）2（H2O）].（H2O）0.5]n （L = pyrazine-1,4-dioxide） and one-dimensional complex 2 [Co（μ-L）Br2（H2O）2]n, have been synthesized with pyrazine-1,4-dioxide as bridging ligands, and their crystal structures were determined by X-ray crystallography. Crystal data for complex 1： monoclinic system, space group C2/c, with a = 23.310（3）, b = 12.2338（17）, c = 10.6075（15） A, β= 110.487（2）°, V = 2833.6（7） A3, Z = 8, C6H9C12CuN3O12.5, Mr = 457.60, Dc = 2.145 g/cm^3, F（000） = 1832 and μ = 1.998 mm^-1; and those for 2： monoclinic system, space group C2/c, with a = 11.012（3）, b = 7.483（2）, c = 11.451（3） A, β = 101.654（4）°, V = 924.2（4） A3, Z = 4, C4HsBr2CoN2O4, Mr = 366.87, Dc = 2.637 g/cm^3, F（000） = 700 and μ = 10.487 mm^-1. 1 shows a two-dimensional sheet structure on the ac plane through the coordination of μ-L bridging ligands with Cu（Ⅱ） ions, while 2 displays a zigzag one-dimensional chain along the c axis via the coordination of μ-L bridging ligand with Co（Ⅱ） ions. Hydrogen bonds in 1 and 2 make the sheets （or chains） connect each other to form a three-dimensional structure.

关键词： Aromatic Dioxide coordination polymers Hydrogen bonds

Ultrafast optical modulation of the fluorescence from a single-photon emitter in silicon carbide

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Photonics Research 2024年第5期12卷 941-946页

作者： MENGTING HE YUJING CAO juNJIE LIN ZHIPING ju BOTAO wu E wu State Key Laboratory of Precision Spectroscopy East China Normal UniversityShanghai 200241China Photon Technology(Zhejiang)Co. Ltd.Jiaxing 314100China National Key Laboratory of Materials for Integrated Circuits Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200000China Department of Physics and Shanghai Key Laboratory for Magnetic Resonance East China Normal UniversityShanghai 200241China Chongqing Key Laboratory of Precision Optics Chongqing Institute of East China Normal UniversityChongqing 401120China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China

The quest for the room-temperature optical transistor based on nonlinearities in single atoms or molecules is attracting a lot of *** this work,a single-photon emitter in cubic silicon carbide is verified that can operate as an optical switch at room temperature under pulsed green laser illumination with a near-infrared pulsed laser as the control *** demonstrated an ultrafast and reversible optical modulation with a high photoluminescence intensity suppression ratio up to 97.9%and a response time as short as 287.9±5.7 *** current development provides insights for high-precision and ultrafast optical switches,with possibilities for integration with emerging electronic installations to realize more intelligent photoelectric integrated devices.

关键词： emitter carbide photon

A buffer overflow detection and defense method based on RiSC-V instruction set extension

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Cybersecurity 2024年第2期7卷 28-43页

作者： chang Liu Yan-jun wu Jing-Zheng wu Chen Zhao Intelligent Software Research Center Institute of SoftwareChinese Academy of SciencesBejingChina University of Chinese Academy of Sciences BeijingChina State Key Laboratory of Computer Science Institute of SoftwareChinese Academy of SciencesBeijingChina

Buffer overflow poses a serious threat to the memory security of modern operating *** overwrites the con-tents of other memory areas by breaking through the buffer capacity limit,destroys the system execution environ-ment,and provides implementation space for various system attacks such as program control flow *** makes it a wide range of harms.A variety of security technologies have been proposed to deal with system security problems including buffer *** example,No eXecute(NX for short)is a memory management technology commonly used in Harvard *** can refuse the execution of code which residing in a specific memory,and can effectively suppress the abnormal impact of buffer overflow on control ***,in recent years,it has also been used in the field of system security,deriving a series of solutions based on NX technology,such as ExecShield,DEP,StackGuard,***,these security solutions often rely too much on the processor archi-tecture so that the protection coverage is insufficient and the accuracy is *** in the emerging system architecture field represented by RiSC-V,there is still a lack of effective solutions for buffer overflow *** the continuous rapid development of the system architecture,it is urgent to develop defense methods that are applicable to different system application environments and oriented to all executable memory spaces to meet the needs of system security ***,we propose BOP,A new system memory security design method based on RISC-V extended instructions,to build a RISC-V buffer overflow detection and defense system and deal with the buffer overflow threat in *** to this method,NX technology can be combined with program control flow analysis,and Nx bit mechanism can be used to manage the executability of memory space,so as to achieve a more granular detection and defense of buffer overflow attacks that may occur in RISC-V system

关键词： RISc-V Operating system security Buffer overflow Control flow hijacking Nx bit Xibop

Ten- year follow- up investigation of stroke risk in systemic lupus erythematosus

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Stroke & Vascular Neurology 2024年第1期9卷 1-7页

作者： Jin-An Huang Ching-Heng Lin Ming-ju wu Yi-Hsing Chen Kuo-Cheng chang Chung-Wei Hou Division of Neurology Neurological InstituteTaichung Veterans General HospitalTaichungTaiwan Department of Health Business Administration Hungkuang UniversityTaichungTaiwan Department of Medical Research Taichung Veterans General HospitalTaichungTaiwan Division of Nephrology Department of Internal MedicineTaichung Veterans General HospitalTaichungTaiwan School of Medicine Chung Shan Medical UniversityTaichungTaiwan College of Medicine National Chung Hsing UniversityTaichungTaiwan Division of Allergy Immunology and RheumatologyDepartment of Internal MedicineTaichung Veterans General HospitalTaichungTaiwan School of Medicine National Yang-Ming Chiao Tung UniversityTaichungTaiwan

Background and purpose To analyse the long-term risk of ischaemic stroke and the clinical effects of antithrombotics on the risk of haemorrhagic stroke in patients with systemic lupus erythematosus(SLE).Methods A retrospective cohort study was conducted using a population-based database taken from Taiwan National Health Insurance Research *** with SLE between 2000 and 2008 were registered and matched with two controls by the index date,age,gender and Charlson Comorbidity Index(CCI).These subjects were followed until either stroke event or 31 December *** HRs(aHRs)for strokes were estimated with Cox regression models,and the cumulative incidence of ischaemic stroke was analysed by log-rank test and Kaplan-Meier survival *** In total,8310 patients with SLE and 16620 patients without SLE were *** general,patients with SLE had higher rates of ischaemic stroke(5.4%vs 3.3%)and haemorrhagic stroke(1.5%vs 0.6%)than in *** multivariate analysis adjusted to age,gender,CCI,urbanisation level and antithrombotics uses,aHRs of all strokes,ischaemic stroke and haemorrhagic stroke were 1.73(95%CI:1.54 to 1.94),1.65(95%CI:1.45 to 1.87)and 2.24(95%CI:1.71 to 2.95),respectively,in patients with *** with SLE were significantly more likely to suffer ischaemic stroke than patients without SLE,even 10 years after SLE diagnosis(6.12%vs 3.50%,p<0.001).Antiplatelet use increased the risk of haemorrhagic stroke in SLE group(aHR=1.74,95%CI:1.18 to 2.57).Conclusions Patients with SLE are at greater risk of developing ischaemic stroke that lasts for 10 *** should be carefully administered to prevent cardiovascular events in patients with SLE due to the risk of haemorrhagic stroke.

关键词： erythematosus diagnosis likely

Generalized load graphical forecasting method based on modal decomposition

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Global Energy Interconnection 2024年第2期7卷 166-178页

作者： Lizhen wu Peixin chang Wei Chen Tingting Pei College of Electrical and Information Engineering Lanzhou University of TechnologyLanzhou 730050P.R.China School of Electrical Data Engineering University of Technology SydneyNSW2007Australia

In a“low-carbon”context,the power load is affected by the coupling of multiple factors,which gradually evolves from the traditional“pure load”to the generalized load with the dual characteristics of“load+power supply.”Traditional time-series forecasting methods are no longer suitable owing to the complexity and uncertainty associated with generalized *** the perspective of image processing,this study proposes a graphical short-term prediction method for generalized loads based on modal ***,the datasets are normalized and feature-filtered by comparing the results of Xtreme gradient boosting,gradient boosted decision tree,and random forest ***,the generalized load data are decomposed into three sets of modalities by modal decomposition,and red,green,and blue(RGB)images are generated using them as the pixel values of the R,G,and B *** generated images are diversified,and an optimized DenseNet neural network was used for training and ***,the base load,wind power,and photovoltaic power generation data are selected,and the characteristic curves of the generalized load scenarios under different permeabilities of wind power and photovoltaic power generation are obtained using the density-based spatial clustering of applications with noise *** on the proposed graphical forecasting method,the feasibility of the generalized load graphical forecasting method is verified by comparing it with the traditional time-series forecasting method.

关键词： Load forecasting Generalized load Image processing DenseNet Modal decomposition

Palladium-catalyzed multi components oxy-aminofluorination and aminofluorination of gem-difluoroalkenes

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Chinese Chemical Letters 2024年第2期35卷 420-425页

作者： Fen wu Xin Li junbiao chang Dachang Bai State Key Laboratory of Antiviral Drugs NMPA Key Laboratory for Research and Evaluation of Innovative DrugKey Laboratory of Green Chemical Media and ReactionsMinistry of EducationSchool of Chemistry and Chemical EngineeringPingyuan LaboratoryHenan Normal UniversityXinxiang 453007China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

Organofluorine compounds are widely used in the realm of drug discovery and material ***,we developed palladium catalyzed intermolecular aminofluorination and oxy-aminofluorination of gem‑difluoroalkenes with N-fluorobenzenesulfonimide(NFSI),in which NFSI was used as the nitrogen source and *** reaction provides an efficient and straightforward synthesis route of a series ofα-trifluoromethyl benzylic ***,three/four components oxy-aminofluorination processes were realized to giveα-trifluoromethyl benzylic ether with a terminal amino group,which proceed through C(sp^(3))-O bond cleavage of easily available ether and simultaneous introduced a fluorine,an amino and an oxy substituent in one pot with excellent *** divergent reactivity not only included the incorporation of one ether molecular,but also much more challenged two ether insertion with excellent selectivity through succession C(sp^(3))-O bonds *** protocol allows for concise synthesis of high value amines with fluoroalkyl-substituents and selectively transformation of easily available ethers by high-valent palladium catalysis.

关键词： Palladium Multi components Aminofluorination Oxy-aminofluorination C(sp^(3))-O bond cleavage

Cell Consistency Evaluation Method Based on Multiple Unsupervised Learning Algorithms

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Big Data Mining and Analytics 2024年第1期7卷 42-54页

作者： Jiang chang Xianglong Gu Jieyun wu Debu Zhang Stellantis China Technology Center Shanghai 200233China

Unsupervised learning algorithms can effectively solve sample *** address battery consistency anomalies in new energy vehicles,we adopt a variety of unsupervised learning algorithms to evaluate and predict the battery consistency of three vehicles using charging fragment data from actual operating *** extract battery-related features,such as the mean of maximum difference,standard deviation,and entropy of batteries and then apply principal component analysis to reduce the dimensionality and record the amount of preserved *** then build models through a collection of unsupervised learning algorithms for the anomaly detection of cell consistency *** also determine whether unsupervised and supervised learning algorithms can address the battery consistency problem and document the parameter tuning *** addition,we compare the prediction effectiveness of charging and discharging features modeled individually and in combination,determine the choice of charging and discharging features to be modeled in combination,and visualize the multidimensional data for fault *** results show that the unsupervised learning algorithm is effective in visualizing and predicting vehicle core conformance faults,and can accurately predict faults in real ***“distance+boxplot”algorithm shows the best performance with a prediction accuracy of 80%,a recall rate of 100%,and an F1 of *** proposed approach can be applied to monitor battery consistency faults in real time and reduce the possibility of disasters arising from consistency faults.

关键词： battery consistency charging segment data unsupervised learning

Sedimentary paleoenvironment and its control on organic matter enrichment in the Mesoproterozoic hydrocarbon source rocks in the Ordos Basin, southern margin of the North China Craton

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Petroleum Science 2024年第4期21卷 2257-2272页

作者： Zhi-Chen wu ju-Ye Shi Tai-Liang Fan Ming Jiang School of Energy Resources China University of Geosciences (Beijing) Key Laboratory of Marine Reservoir Evolution and Hydrocarbon Enrichment Mechanism Ministry of Education China University of Geosciences (Beijing)

The black shale of the Mesoproterozoic Cuizhuang Formation in the changcheng System in Yongji city,North China Craton, is a potential source rock. Understanding the organic matter enrichment mechanism is crucial for evaluating source rock resources and understanding oil and gas accumulation *** this study, we evaluated the sedimentary paleoenvironment and organic matter enrichment mechanisms of shale using thin section observations, mineral composition analysis, organic geochemistry, and elemental geochemistry. We found significant differences in the sedimentary paleoenvironment and organic matter enrichment mechanisms between the lower Cuizhuang Formation and the Beidajian Formation shale. The Cuizhuang Formation was deposited in a late-stage, restricted basin environment during the rift phase, and elemental and geochemical indicators showed that the Cuizhuang Formation was in a suboxic-anoxic water environment, that was influenced by a warm and humid paleoclimate and submarine hydrothermal activities, which promoted the accumulation of organic matter. However, the enrichment of organic matter in the Cuizhuang Formation was mainly controlled by redox *** formation of suboxic-anoxic water environments may be closely related to the warm and humid paleoclimate and submarine hydrothermal activities. Warm conditions promote continental weathering and increase marine productivity, thereby consuming oxygen in the bottom water. Moreover, acidic hydrothermal activity also helps to establish an anoxic environment. Our results reveal the effects controlling various coupled mechanisms dominated by redox conditions, which may explain the development of source rocks in the Cuizhuang Formation.

关键词： Cuizhuang formation Paleoproterozoic source rocks Marine productivity Paleoenvironments Submarine hydrothermal activity Organic matter enrichment