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Journal of Environmental Sciences 2024年第7期141卷 330-342页

作者： Zi-Han Wang Chun-Hua Huang zhi-Sheng Liu Li Mao Ben-Zhan zhu State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China College of Environment and Resources University of Chinese Academy of SciencesBeijing 100049China

We have found recently that two-step intrinsic hydroxyl radical(·OH)-dependent chemiluminescence(CL)could be produced by carcinogenic tetrahaloquinone and H_(2)O_(2).However,the first-step CL was too fast to clearly detect the stepwise generation of·OH and CL,and to distinguish the exact dividing point between the first-step and second-step *** we found that,extremely clear two-step intrinsic CL could be produced by the relative slow reaction of tetrabromohydroquinone(TBHQ)with H_(2)O_(2),which was directly dependent on the two-step·OH ***,the second-step,but not the first-step CL production of TBHQ/H_(2)O_(2)(CRET donor)was markedly enhanced by fluorescein(a typical xanthene dye,CRET acceptor)through a unique chemiluminescence resonance energy transfer(CRET)*** novel CRET system of TBHQ/H_(2)O_(2)/fluorescein was successfully applied for the sensitive detection of TBHQ with the detection limit as low as 2.5μmol/*** findings will help to develop more sensitive and highly efficient CL or CRET systems and specific CL sensor to detect the carcinogenic haloquinones,which may have broad environmental applications.

关键词： Two-step chemiluminescence Bromohydroquinone Hydrogen peroxide Hydroxyl radical CRET

Surface-state controlled synthesis of hydrophobic and hydrophilic carbon dots

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Nano Research 2024年第5期17卷 4391-4399页

作者： Chan Wang yuan Fang Mi Zhang Huan zhuo Qijun Song Han zhu Key Laboratory of Synthetic and Biological Colloids Ministry of EducationSchool of Chemical and Material EngineeringJiangnan UniversityWuxi 214122China Jiangsu Snow Leopard Household Chemical Co. Ltd.Wuxi 214400China

It is of great significance to synthesize carbon dots(CDs)with desirable hydrophilicity for the ever-growing application of CDs in different *** this study,the hydrophilic and hydrophobic CDs were facilely prepared by solvothermal treatment of o-dihydroxybenzene and urea in N,N-dimethylformamide(DMF).Optimization experiments revealed that the solvothermal temperature has a great impact on the surface states of the *** hydrophobic CDs with a contact angle of 110.7°was obtained at 200℃.The structural and optical characterizations,along with theoretical calculations elucidated that the lipophilic nature of the CDs was resulting from the formation of polymer *** presence of extended conjugated sp^(2)-domains and amino groups contributed to the red emission of the CDs synthesized at low reaction temperatures(160-200℃).With the further increase of solvothermal temperature,the hydrophobic CDs were gradually transformed to the hydrophilic state accompanying the blue shift of the fluorescence of the *** highly hydrophilic CDs with a contact angle of 25.9°were obtained at 240℃ due to the increased formation of hydrophilic functional groups on the surface of *** red emissive CDs exhibited a sensitive color and fluorescence response to ethanol content while the fluorescence of the blue emissive CDs remained *** combining the two kinds of CDs,a dual-emission sensor was constructed,which was successfully applied for the evaluation of the alcoholic strength in commercial Baijiu commodities in both fluorometric and colorimetric modes.

关键词： carbon dots surface chemistry hydrophilicity and hydrophobicity solvothermal temperature alcoholic strength evaluation

Preparation of PVA/GO/h-BN Janus Film with High Thermal Conductivity and Excellent Flexibility via a Density Deposition Self-assembly Method

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Chinese Journal of Polymer Science 2024年第8期42卷 1217-1226页

作者： Fang-Hua Luo zhi-Tao Dong Guo-Hua Chen Chen Ma Huai-yuan Wang College of Chemistry and Chemical Engineering Northeast Petroleum UniversityDaqing 163318China College of Materials Science and Engineering Huaqiao UniversityXiamen 361000China School of Chemical Engineering and Technology and State Key Laboratory for Chemical Engineering Tianjin UniversityTianjin 300350China

Janus films with asymmetric physical/chemical properties have attracted con siderable attention due to their promising applications in personal thermal management,electronic skin s,sensors,actuators,***,traditional methods for fabricating Janus films conventionally need the assistance of an interface or auxiliary equipment,which are usually complex and ***,flexible poly(vinyl alcohol)(PVA)/graphene oxide(GO)/h-BN(recorded as PVA/GO/h-BN)Janus films with thermally,optically,and electrically anisotropic properties are fabricated by a simple density deposition self-assem bly method,which just utilizes the density difference between GO and h-BN during water *** results show that the two sides of the acquired Janus films have obvious asymmetric *** the original state of the PVA/GO/h-BN Janus films,the thermal conductivity of the GO side(10.06 W·m^(-1)·K^(-1))is generally lower than that of the h-BN side(10.48W·m^(-1)·K^(-1)).But after GO is reduced,the thermal conductivity of the rGO side reaches 12.17 W·m^(-1)·K^(-1),surpassing that of the h-BN *** addition,the relative reflectance of the h-BN side of Janus film is also significantly higher than that of the rGO side,and the su rface resistance difference between the two sides is about 4 orders of *** prepared PVA/GO/h-BN Janus films show great application potential in human thermal management,light conversion switches,and electronic *** study provides a simple and versatile strategy for fabricating Janus films with multifunctional(such as thermal,optical,and electrical)anisotropies.

关键词： Janus films PVA/GO/h-BN Density deposition self-assembly method

A Heuristic Radiomics Feature Selection Method Based on Frequency Iteration and Multi-Supervised Training Mode

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Computers, Materials & Continua 2024年第5期79卷 2277-2293页

作者： zhigao Zeng Aoting Tang Shengqiu Yi Xinpan yuan Yanhui zhu School of Computer Hunan University of TechnologyZhuzhou412007China Hunan Key Laboratory of Intelligent Information Perception and Processing Technology Zhuzhou412007China

Radiomics is a non-invasive method for extracting quantitative and higher-dimensional features from medical images for *** has received great attention due to its huge application prospects in recent *** can know that the number of features selected by the existing radiomics feature selectionmethods is basically about *** this paper,a heuristic feature selection method based on frequency iteration and multiple supervised training mode is *** on the combination between features,it decomposes all features layer by layer to select the optimal features for each layer,then fuses the optimal features to form a local optimal group layer by layer and iterates to the global optimal combination *** with the currentmethod with the best prediction performance in the three data sets,thismethod proposed in this paper can reduce the number of features fromabout ten to about three without losing classification accuracy and even significantly improving classification *** proposed method has better interpretability and generalization ability,which gives it great potential in the feature selection of radiomics.

关键词： Radiomics feature selection machine learning metaheuristic

Impact of EnKF assimilating Himawari-8 all-sky infrared radiance on the forecasting of a warm-sector rainstorm event

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Science China Earth Sciences 2024年第10期67卷 3110-3127页

作者： Shanshan LOU Lei zhu Xuexing QIU Guangzhou CHEN Song yuan Shengnan ZHOU Anhui Meteorological Observatory Hefei 230031China Key Laboratory of Meteorological Disaster Ministry of Education(KLME)Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)Joint International Research Laboratory of Climate and Environment Change(ILCEC)Nanjing University of Information Science&TechnologyNanjing 210044China Huaihe River Basin Meteorological Center Hefei 230031China Shouxian National Climatology Observatory Huaihe River Basin Typical Farm Eco-Meteorological Experiment Field of CMAShouxian National Comprehensive Meteorological Observation Special Experimental OutfieldShouxian 232200China Anhui Province Key Laboratory of Atmospheric Science and Satellite Remote Sensing Hefei 230031China

Warm-sector rainstorms are highly localized events, with weather systems and triggering mechanisms are not obvious,leading to limited forecasting capabilities in numerical models. Based on the ensemble Kalman filter(PSU-En KF) assimilation system and the regional mesoscale model WRF, this study conducted a simulation experiment assimilating all-sky infrared(IR)radiance for a warm-sector rainstorm in East China and investigated the positive impact of assimilating the Himawari-8 moisture channel all-sky IR radiance on the forecast of the rainstorm. Results indicate that hourly cycling assimilation of all-sky IR radiance can significantly improve the forecast accuracy of this warm-sector rainstorm. There is a notable increase in the Threat Score(TS), with the simulated location and intensity of the 3-hour precipitation aligning more closely with observations. These improvements result from the assimilation of cloud-affected radiance, which introduces more mesoscale convective information into the model's initial fields. The adjustments include enhancements to the moisture field, such as increased humidity and moisture transport, and modifications to the wind field, including the intrusion of mid-level cold air and the strengthening of lowlevel convergent shear. These factors are critical in improving the forecast of this warm-sector rainstorm event.

关键词： Ensemble Kalman filter WRF model Himawari-8 All-sky radiance Warm-sector rainstorm

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A function-based behavioral modeling method for air combat simulation

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Journal of Systems Engineering and Electronics 2024年第4期35卷 945-954页

作者： WANG Tao zhu zhi ZHOU Xin JING Tian CHEN Wei College of Systems Engineering National University of Defense TechnologyChangsha 410073China Institute of Communication and Navigation Air Force Research AcademyBeijing 100085China

Today’s air combat has reached a high level of uncertainty where continuous or discrete variables with crisp values cannot be properly represented using fuzzy sets. With a set of membership functions, fuzzy logic is well-suited to tackle such complex states and actions. However, it is not necessary to fuzzify the variables that have definite discrete ***, the aim of this study is to improve the level of model abstraction by proposing multiple levels of cascaded hierarchical structures from the perspective of function, namely, the functional decision tree. This method is developed to represent behavioral modeling of air combat systems, and its metamodel,execution mechanism, and code generation can provide a sound basis for function-based behavioral modeling. As a proof of concept, an air combat simulation is developed to validate this method and the results show that the fighter Alpha built using the proposed framework provides better performance than that using default scripts.

关键词： air combat behavioral modeling intelligent agent

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基于鲁棒有限时控制的混沌系统的同步

物理学报 2005年第6期54卷 2574-2579页

作者：高铁杠陈增强袁祉南开大学信息技术科学学院自动化系

通过构造快速滑模控制器,实现了混沌系统的有限时同步,指出许多混沌系统经过状态变换后,都可以通过快速收敛的有限时控制器在有限时间内实现驱动系统和响应系统的完全同步,并以陈氏混沌系统和四阶细胞神经网络超混沌系统为例进行了系统... 详细信息

通过构造快速滑模控制器,实现了混沌系统的有限时同步,指出许多混沌系统经过状态变换后,都可以通过快速收敛的有限时控制器在有限时间内实现驱动系统和响应系统的完全同步,并以陈氏混沌系统和四阶细胞神经网络超混沌系统为例进行了系统仿真.结果显示,该有限时控制器不仅具有良好的性能,而且具备较强的鲁棒性.

关键词：鲁棒控制有限时同步混沌系统非线性神经网络

Study of the relationship between the local geometric structure and the stability of La_(0.6)Sr_(0.4)MnO_(3-δ) and La_(0.6)Sr_(0.4)FeO_(3-δ)electrodes

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Nuclear Science and Techniques 2019年第2期30卷 101-108页

作者： Cheng-zhi Guan Jing Zhou Hong-Liang Bao Cheng Peng Xiao Lin Guo-Ping Xiao Jian-Qiang Wang zhi-yuan zhu Department of Molten Salt Chemistry and Engineering Key Laboratory of Interfacial Physics and TechnologyShanghai Institute of Applied PhysicsChinese Academy of Sciences University of Chinese Academy of Sciences

Sr-substituted ABO_3 perovskite oxides such as La_(0.6) Sr_(0.4 )Mn_(O3-δ)(LSM) and La_(0.6) Sr_(0.4) FeO_(3-δ)(LSF) are widely used as oxygen electrode materials in solid oxide cells. The substituted Sr is not adequately stable under the operating conditions, because of the surface segregation of Sr. Herein, we focused on investigating the relationship between the local geometric structure due to Sr substitution and stability of LSM and LSF. We characterized the local geometric structure of Sr atoms via X-ray absorption spectroscopy. A greater Debye-Waller factor and a longer bond length of both the second and third Sr-O shells were observed in LSF, which demonstrates that LSF has a higher local structural disorder and that Sr in LSF requires less energy to segregate. After 20 h of heat treatment in the presence of a Fe-Cr alloy interconnect, the Sr/La molar ratio on LSF was observed to be much larger than that on LSM. This result unequivocally suggests that Sr in LSF is not as stable as in LSM, and the reaction between Sr and Cr accelerates the Sr surface segregation in LSF.

关键词： Solid oxide cell Perovskite Strontium surface segregation X-ray absorption spectroscopy Chromium poisoning

The NAC Transcription Factor ANAC089 Modulates Seed Vigor through the ABI5-VTC2 Module in Arabidopsis thaliana

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Phyton-International Journal of Experimental Botany 2024年第6期93卷 1101-1116页

作者： yuan Tian Lulu zhi Ping Li Xiangyang Hu Shanghai Key Laboratory of Bio-Energy Crops School of Life SciencesShanghai UniversityShanghai200444China

Seed viability is an essential feature for genetic resource conservation as well as sustainable crop ***-term storage induces seed viability deterioration or seed aging,accompanied by the accumulation of toxic reactive oxygen species(ROS)to suppress seed *** deterioration treatment(CDT)is a gen-eral approach for mimicking seed *** transcription factor ANAC089 was previously reported to modulate seed primary *** this study,we evaluated the ability of ANAC089 to control seed viability during *** with that in the wild-type line,the mutation of ANAC089 signiﬁcantly increased H_(2)O_(2),thereby reducing seed viability after CDT,while the overexpression of ANAC089 reduced H_(2)O_(2) and improved seed long-evity,indicating a critical role for ANAC089 in maintaining seed viability through H_(2)O_(2) signaling.A series of stu-dies have shown that ANAC089 targets and negatively regulates the level of ABI5,an important transmitter of abscisic acid(ABA)signals,to affect seed viability after ***,ABI5 negatively regulated the expres-sion of VTC2,which is involved in the biosynthesis of the antioxidant ascorbic acid and H_(2)O_(2) *** a result,ANAC089 attenuates the generation of H_(2)O_(2),thereby enhancing seed viability through the ABI5-VTC2 module during the seed aging *** together,our results reveal a novel mechanism by which ANAC089 enhances seed viability by coordinating ABI5 and VTC2 expression,ultimately preventing the overac-cumulation of H_(2)O_(2),which would have led to reduced seed viability.

关键词： Arabidopsis seed aging ANAC089 ABI5 VTC2 H_(2)O_(2)

Impact of baseline hepatitis B virus viral load on the long-term prognosis of advanced hepatocellular carcinoma treated with immunotherapy

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World Journal of Gastrointestinal Oncology 2024年第6期16卷 2504-2519页

作者： Di Pan Hao-Nan Liu zhi-yuan Yao Xiao-Xiao Chen Yu-Qi Li Jing-Jing zhu Zheng-Xiang Han Xiao-Bing Qin Department of Oncology The Affiliated Hospital of Xuzhou Medical UniversityXuzhou 221000Jiangsu ProvinceChina

BACKGROUND Although the combination of lenvatinib and PD-1 inhibitors has become the standard regimen for the treatment of advanced hepatocellular carcinoma(HCC),real data on the impact of baseline hepatitis B virus(HBV)-DNA levels on the clinical efficacy of this regimen is still *** To evaluate the effectiveness of camrelizumab combined with lenvatinib in patients with HCC at varying levels of *** One hundred and twenty patients with HCC who received camrelizumab and lenvatinib treatment were categorized into two cohorts:HBV-DNA≤2000(n=66)and HBV-DNA>2000(n=54).The main outcomes measured were overall survival(OS)and progression-free survival(PFS),while additional outcomes included the rate of objective response rate(ORR),disease control rate(DCR),and any negative *** proportional hazards regression analysis revealed independent predictors of OS,leading to the creation of a nomogram incorporating these *** The median PFS was 8.32 months for the HBV-DNA≤2000 group,which was similar to the 7.80 months observed for the HBV DNA>2000 group(P=0.88).Likewise,there was no notable variation in the median OS between the two groups,with durations of 13.30 and 14.20 months respectively(P=0.14).The ORR and DCR were compared between the two groups,showing ORR of 19.70%vs 33.33%(P=0.09)and DCR of 72.73%vs 74.07%(P=0.87).The nomogram emphasized the importance of antiviral treatment as the main predictor of patient results,with portal vein tumor thrombus and Barcelona Clinic Liver Cancer staging following closely *** The clinical outcomes of patients with HBV-associated HCC treated with camrelizumab in combination with lenvatinib are not significantly affected by HBV viral load.

关键词： Hepatitis B virus Hepatocellular carcinoma Camrelizumab Lenvatinib Efficacy