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A facile method to fabricate high-quality perovskite nanocrystals based on single crystal powder

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Nano Research 2019年第10期12卷 2640-2645页

作者： Jin-Feng Liao Yi-Xin Chen Jun-Hua Wei ya-Ting Cai Xu-Dong Wang yang-Fan Xu Dai-bin Kuang MOE Key Laboratory of Bioinorganic and Synthetic Chemistry Lehn Institute of Functional MaterialsSchool of ChemistrySun Yat-sen UniversityGuangzhou 510275China

Although great advancements have been successfully achieved in ligand-assisted reprecipitation strategy(LARP)towards lead halide perovskite nano crystals(NCs)syn thesis,it still remains challe nging to develop bright and stable iodide-based perovskite NC via facile ***,striki ngly bright MAPbl3 NCs with photoluminesce nee qua ntum yield(PLQY)as high as 79%are synthesized via replacing the raw material(MAI and Pbh)with MAPbl3 crystal powder during LARP *** has been found that crystal powder derived MAPbl3 NCs are more iodide-rich compared with that based on raw material,which is favorable to passivate the surface trap ***,femtosecond transient absorption spectroscopies and space charge limited current measurements have corroborated that the trap density is much less in crystal powder resulted MAPbl3 *** analyses indicate stronger solvation with reduced precursor colloid size has been observed in crystal powder derived precursor solution probably due to the formation of *** work has provided a facile but valid method to enhance the photoluminesce nee of perovskite NC via modulati ng the beginning precursor solution.

关键词： MAPbh nanocrystal perovskite transient absorption light emitting

Properties of phosphate glass waste forms containing fluorides from a molten salt reactor

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Nuclear Science and Techniques 2016年第3期27卷 96-102页

作者： ya-Ping Sun Xiao-bin Xia yan-Bo Qiao Zhong-Qi Zhao Hong-Jun Ma Xue-yang Liu Zheng-Hua Qian Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China

Radioactive fluoride wastes are generated during the operation of molten salt reactors(MSRs) and reprocessing of their spent *** of these wastes in borosilicate glass is not feasible because of the very low solubility of fluorides in this *** candidates are thus an active topic of research including phosphatebased glasses,crystalline ceramics,and hybrid glass-ceramic *** this study,mixed fluorides were employed as simulated MSRs waste and incorporated into sodium aluminophosphate glass to obtain phosphate-based waste *** waste forms were characterized by X-ray diffraction,Raman spectroscopy,and scanning electron *** tests were performed in deionized water using the product consistency test A *** study demonstrates that up to 20 mol%of simulated radioactive waste can be introduced into the NaA1 P glass matrix,and the chemical durability is much better than that of *** addition of Fe_2O_3 in the NaAlP glass matrix results in increases of the chemical durability at the expense of fluoride loading(to 6.4 mol%).Phosphate glass vitrification of radioactive waste containing fluorides is a potential method to treat and dispose of MSR wastes.

关键词：磷酸盐玻璃玻璃废物含氟化物放射性废物处理扫描电子显微镜熔盐堆硼硅酸盐玻璃化学耐久性

Distributed fault diagnosis observer for multi-agent system against actuator and sensor faults

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Journal of Systems Engineering and Electronics 2023年第3期34卷 766-774页

作者： YE Zhengyu JIANG bin CHENG Yuehua YU Ziquan yang yang College of Automation Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China

Component failures can cause multi-agent system(MAS)performance degradation and even disasters,which provokes the demand of the fault diagnosis method.A distributed sliding mode observer-based fault diagnosis method for MAS is developed in presence of actuator and sensor ***,the actuator and sensor faults are extended to the system state,and the system is transformed into a descriptor system ***,a sliding mode-based distributed unknown input observer is proposed to estimate the extended ***,adaptive laws are introduced to adjust the observer ***,the effectiveness of the proposed method is demonstrated with numerical simulations.

关键词： multi-agent system(MAS) sensor fault actuator fault unknown input observer sliding mode fault diagnosis

Alternaria toxin-induced resistance against rose aphids and olfactory response of aphids to toxin-induced volatiles of rose plants

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2012年第2期13卷 126-135页

作者： Fa-zhong yang Li LI bin yang Key Laboratory of Forest Disaster Warning and Control in Yunnan Province Southwest Forestry UniversityKunming 650224China

The search for active toxins for managing weeds or plant diseases is believed to be a promising avenue of investigation. However, the effects of Alternaria toxins on insects have just begun to be investigated. Bioactivities of toxins from four strains of Altemaria alternata on Rosa chinensis and rose aphid Macrosiphum rosivorum were tested in the present study. At a concentration of 50.0 pg/ml, the crude extract （toxin） of strain 7484 was found not to be harmful to rose plants with excised leaf-puncture method （P≥0.079）, and rose plants showed enhanced resistance to rose aphids when this Altemaria toxin was sprayed on the plants （P≤0.001）. However, this toxin caused no detrimental effects on aphids in insecticidal bioassay at a concentration of 10.0 to 160.0 μg/ml （P≥0.096）. Therefore, the Alternaria toxin had significantly induced the resistance of rose plants against rose aphids, demonstrating that the resistance mechanism triggered by the Altemaria toxin in the rose plant may also be used by the plant to defend itself against insects. Further bioassays aimed to discover the olfactory responses of aphids to the toxin-induced volatiles of host plants. The aphids were significantly more attracted to both volatiles emitted and collected from control rose plants than to both volatiles emitted and collected from the toxin-treated rose plants （P≤0.014）. This result showed that the toxin-induced resistance related to the volatile changes of host plants.

关键词： Alternaria altemata Macrosiphum rosivorum Rosa chinensis Toxin Plant resistance Olfactory response Volatile Headspace collection

Polyprenylated acylphloroglucinols from the fruits of Hypericum henryi

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Science China Chemistry 2016年第9期59卷 1216-1223页

作者： yang Liao Shu-ya yang Xiao-Nian Li Xing-Wei yang Gang Xu State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of Botany Chinese Academy of Sciences Kunming 650201 China University of Chinese Academy of Sciences Beijing 100049 China

Hyphenrones R–X(1–7), seven new polyprenylated acylphloroglucinols derivatives, were isolated from the fruits of Hypericum henryi, together with eight know analogues. Compounds 1 and 2 were elucidated to possess complex caged skeleton, while compounds 3–6 shared a common 3,9-epoxy moiety deriving from the normal polyprenylated acylphloroglucinols with a bicyclo[3.3.1]nonane-2,4,9-trione core. The new structures were elucidated on the basis of the interpretation of nuclear magnetic resonance(NMR) data, circular dichroism(CD) comparison, and single-crystal X-ray diffraction. In the bioassay, several compounds exhibited inhibitory activities against human tumor cell lines in vitro.

关键词： polyprenylated acylphloroglucinols Hypericum henryi hyphenrones R-X antitumor

Lycopene exerts anti-inflammatory effect to inhibit prostate cancer progression

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Asian Journal of Andrology 2019年第1期21卷 80-85页

作者： Li-Ning Jiang ya-bin Liu bing-Hui Li Department of Surgery II Fourth Hospital of Hebei Medical UniversityShijiazhuang 050011China Department of Urology Surgery I Cangzhou Central Hospita Cangzhou 061000China

Lycopene is a natural compound that alleviates oxidative stress and inflammation,exerting therapeutic effects in a number of *** aim of this study is to investigate the efficacy of lycopene in inhibiting prostate *** viability assays indicated the dose-and time-dependent toxicity of lycopene in prostate cancer *** V/propidium iodide double-staining assays revealed the strong apoptotic effects of *** levels of inflammatory factors,including interleukin-1 (ILl),IL6,ILS,and tumor necrosis factor-α(TNF-α),in lycopene-treated cells were also reduced by lycopene *** the increasing dose of lycopene,the survival of mice bearing prostate cancer xenografts was significantly improved (P <0.01),and the tumor burden was significantly reduced (P <0.01).Our results indicate that lycopene is a promising chemotherapy drug,which inhibits prostate cancer progression by suppressing the inflammatory response.

关键词： dietary supplement inflammation lycopene prostate cancer

Room-temperature-densified H_(3)BO_(3) microwave dielectric ceramics with ultra-low permittivity and ultra-high Qf value

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Journal of Materiomics 2020年第2期6卷 233-239页

作者： Wen bin Hong Lei Li Han yan Shu ya Wu Hang Sheng yang Xiang Ming Chen Laboratory of Dielectric Materials School of Materials Science and EngineeringZhejiang UniversityHangzhou310027China

With the rapid development of mobile communication technology towards 5G and 6G,the microwave dielectric materials with ultra-low permittivity and ultra-high Qf value are urgently ***,the excellent microwave dielectric properties are reported in H3BO3 ceramics with the molecular crystal structure,whose permittivity(2.84)and density(1.46 g/cm^(3))are record-low among the low-loss *** ultra-high Qf value of 146,000 GHz(or the ultra-low dielectric loss of 1.03×10^(-4) at 15 GHz)is also ***,the H_(3)BO_(3) ceramics can be densified at room temperature by a simple cold sintering process in a short time of 10 min,and this brings many advantages for the integration with microwave *** large molecule volume originating from the molecular crystal structure and the low dielectric polarizabilities of H^(+) and B^(3+) are responsible for the ultra-low permittivity of H_(3)BO_(3) ceramics,and more microwave dielectric materials with ultra-low permittivity and ultra-high Qf value are expected to be explored in the molecular crystals.

关键词： Boric acid Microwave dielectric ceramics Room-temperature cold sintering Ultra-low permittivity

Using HyperCoal to prepare metallurgical coal briquettes via hot-pressing

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International Journal of Minerals,Metallurgy and Materials 2019年第5期26卷 547-554页

作者： ya-jie Wang Hai-bin Zuo Jun Zhao Wan-long Zhang State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing

HyperCoal was prepared from low-rank coal via high-temperature solvent extraction with N-methylpyrrolidone as an extraction solvent and a liquid-to-solid ratio of 50 mL/g in a high-temperature and high-pressure reactor. When HyperCoal was used as a binder and pulverized coal was used as the raw material, the compressive strength of the hot-pressed briquettes(each with a diameter of 20 mm and mass of 5 g) under different conditions was studied using a hot-pressing mold and a high-temperature furnace. The compressive strength of the hot-pressed briquettes was substantially improved and reached 436 N when the holding time period was 15 min, the hot-pressing temperature was 673 K, and the HyperCoal content, was 15 wt%. Changes in the carbonaceous structure, as reflected by the intensity ratio between the Raman G-and D-bands(IG/ID), strongly affected the compressive strength of hot-pressed briquettes prepared at different hot-pressing temperatures. Compared with cold-pressed briquettes, hot-pressed briquettes have many advantages, including high compressive strength, low ash content, high moisture resistance, and good thermal stability; thus, we expect that hot-pressed briquettes will have broad application prospects.

关键词： HyperCoal coal briquette compressive strength binder hot-pressing

Corrosion evolution and behaviour of Al-2.1Mg-1.6Si alloy in chloride media

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Rare Metals 2021年第4期40卷 908-919页

作者： ya-ya Zheng bing-Hui Luo Chuan He yang Gao Zhen-Hai Bai College of Materials Science and Engineering Central South UniversityChangsha 410083China Key Laboratory of Safety Design and Reliability Technology for Engineering Vehicle Changsha University of Science and TechnologyChangsha 410114China

Owing to the importance of finding better methods and technologies for protecting against corrosion of aluminium alloys,research into the electrochemical characteristics of the corrosion is an ongoing *** this paper,the corrosion behaviour of Al-Mg-Si alloys in 3.5 wt% NaCl solution was investigated using multiple methods,including scanning electron microscopy(SEM),transmission electron microscopy(TEM),potentiodynamic polarisation measurement and electrochemical impedance spectroscopy(EIS).The results suggest that corrosion begins with dealloying of Mg,followed by conversion of MgSi particles into Al-Fe-Mn-Si *** corrosion rate increased until it reached a peak and then *** increase in the corrosion rate may be attributed to an increased electrochemical driving force,which is produced by anodic dissolution between the matrix and residual MgSi ***,the thin re-deposited layer of inert elements also plays an important role in accelerating the anodic process of the corrosion *** passivated corrosion pit and narrowed intergranular corrosion(IGC)pathway cause the area of active dissolution to decrease,thus reducing the corrosion rate.

关键词： Al-Mg-Si alloys Corrosion behaviour Electrochemical Corrosion rate IGC corrosion pathway