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Al-modified yolk-shell silica particle-supported NiMo catalysts for ultradeep hydrodesulfurization of dibenzothiophene and 4,6-dimethyldibenzothiophene:Efficient accessibility of active sites and suitable acidity

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Petroleum Science 2024年第1期21卷 654-666页

作者： ke Yu Wei-Min kong Zhen Zhao Ai-Jun Duan Lian kong Xi-Long Wang State key Laboratory of Heavy Oil Processing China University of PetroleumBeijing102249China Institute of Catalysis for Energy and Environment College of Chemistry and Chemical EngineeringShenyang Normal UniversityShenyang 110034LiaoningChina

Yolk-shell SiO2 particles(YP)with center-radial meso-channels were fabricated through a simple and effective method.Al-containing YP-supported NiMo catalysts with different Al amounts(NiMo/AYP-x,x=Si/Al molar proportion)were prepared and dibenzothiophene(DBT)and 4,6-dimethyl-dibenzothiophene(4,6-DMDBT)were employed as the probes to evaluate the hydrodesulfurization(HDS)catalytic performance.The as-prepared AYP-x carriers and corresponding catalysts were characterized by some advanced characterizations to obtain deeper correlations between physicochemical properties and the HDS performance.The average pore sizes of series AYP-x supports are above 6.0 nm,which favors the mass transfer of organic sulfides.The cavity between the yolk and the shell is beneficial for the enrichment of S-containing compounds and the accessibility between reactants and active metals.Aluminum embedded into the silica framework could facilitate the formation of Lewis(L)and Brønsted(B)acid sites and adjust the metal-support interaction(MSI).Among all the as-synthesized catalysts,NiMo/AYP-20 catalyst shows the highest HDS activities.The improved HDS activity of NiMo/AYP-20 catalyst is attributed to the perfect combination of excellent structural properties of the yolk-shell mesoporous silica,enhanced acidity,moderate MSI,and good accessibility/dispersion of active components.

关键词： Al-containing yolk-shell silica particles Accessibility Acidity Metal-support interaction Hydrodesulfurization

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Geochemical fractionation and potential release behaviour of heavy metals in lead–zinc smelting soils

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Journal of Environmental Sciences 2024年第5期139卷 1-11页

作者： Xinghua Luo Chao xiang Chuan Wu Wenyan Gao Wenshun ke Jiaqing Zeng Waichin Li Shengguo Xue School of Metallurgy and Environment Central South UniversityChangsha 410083China Chinese National Engineering Research Center for Control and Treatment of Heavy Metal Pollution Central South UniversityChangsha 410083China Department of Science and Environmental Studies The Education University of Hong KongHong Kong 999077China

The lack of understanding of heavy metal speciation and solubility control mechanisms in smelting soils limits the effective pollution control.In this study smelting soils were investigated by an advanced mineralogical analysis(AMICS),leaching tests and thermodynamic modelling.The aims were to identify the partitioning and release behaviour of Pb,Zn,Cd and As.The integration of multiple techniques was necessary and displayed coherent results.In addition to the residual fraction,Pb and Zn were predominantly associated with reducible fractions,and As primarily existed as the crystalline iron oxide-bound fractions.AMICS quantitative analysis further confirmed that Fe oxyhydroxides were the common dominant phase for As,Cd,Pb and Zn.In addition,a metal arsenate(paulmooreite)was an important mineral host for Pb and As.The pH-stat leaching indicted that the release of Pb,Zn and Cd increased towards low pH values while release of As increased towards high p H values.The separate leaching schemes were associated with the geochemical behaviour under the control of minerals and were confirmed by thermodynamic modelling.PHREEQC calculations suggested that the formation of arsenate minerals(schultenite,mimetite and koritnigite)and the binding to Fe oxyhydroxides synchronously controlled the release of Pb,Zn,Cd and As.Our results emphasized the governing role of Fe oxyhydroxides and secondary insoluble minerals in natural attenuation of heavy metals,which provides a novelty strategy for the stabilization of multi-metals in smelting sites.

关键词： Smelting soils Heavy metal Fractionation AMICS Geochemical modelling

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NbB_(2)Modified Al-Cu Alloys Fabricated by Freeze-Ablation Casting under High Cooling Rate Solidification

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Acta Metallurgica Sinica(English Letters) 2024年第5期37卷 921-938页

作者： xiang kong Yu Wang Hong Xu Haotian Fan Yuewu Zheng Beibei Xie School of Materials Science and Engineering North University of ChinaTaiyuan 030051China

At present,improving the properties of aluminum alloys is generally achieved by increasing the cooling rate of the melt and adding micro-nano particles.Controlling the cooling rate of the melt to improve the refining effect of grain refiner is still a difficult problem in the aluminum alloy casting industry.An innovative and environmentally friendly casting process,known as freeze ablation,was introduced during the preparation of an Al–NbB_(2) intermediate alloy.This process significantly enhanced the cooling rate of the melt.The results indicated that the Al–NbB_(2) intermediate alloy produced under high cooling rates had a noticeable refining effect on Al–Cu alloys,with smaller NbB2 particles demonstrating superior refining performance.The average grain size of the refined Al–Cu alloy decreased from 154 to 69μm,the tensile strength increased by 12%,the fluidity increased by 18.4%,and the hot tearing index decreased from 144 to 12.The matching degree between NbB_(2) andα-Al was calculated using high-resolution transmission electron microscopy and the edge-to-edge model.It was found that the atomic interplanar spacing and the interatomic spacing mismatch between NbB_(2)’splane and Al were both less than 10%,which further proved that NbB2 could serve as an effective nucleation site forα-Al grains to achieve grain refinement.

关键词： Grain refinement Freeze ablation Particle size control Mechanical properties Process properties

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Intestinal malrotation complicated with gastric cancer: A case report

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World Journal of Clinical Cases 2024年第1期12卷 210-216页

作者： xiang-Hao Jia Shuai kong Xin-Xin Gao Bi-Cong Cong Chun-Ning Zheng School of Clinical Medicine Weifang Medical UniversityWeifang 261053Shandong ProvinceChina Department of Gastrointestinal Surgery Provincial Hospital Affiliated to Shandong First Medical UniversityJinan 250000Shandong ProvinceChina

BACKGROUND Intestinal malrotation is a congenital defect of embryonic development caused by various teratogenic factors.In this condition,the intestinal tube,along with the superior mesenteric artery serving as the axis for the counterclockwise movement,is incomplete or abnormally rotated due to incomplete attachment of the mesentery and abnormal intestinal tube position.Such a case is usually asymp-tomatic and thus difficult to detect.Therefore,similar variant malformations are only found during an operation required for other abdominal diseases.CASE SUMMARY An elderly male patient was admitted to the hospital due to gastric cancer.An abdominal computed tomography(CT)scan with contrast revealed that the ascending and descending colon were parallel on the right side of the abdominal cavity,while the sigmoid colon extended into the right iliac fossa,allowing the diagnosis of congenital midgut malrotation.Following thorough preoperative preparation,the patient underwent laparoscopic radical gastrectomy to treat his gastric cancer.Intraoperatively,an exploration of the abdominal cavity uncovered the absence of the transverse colon.The distal colon at the hepatic flexure,along with the ascending colon,extended into the right iliac fossa,where it continued as the sigmoid colon.As planned,the laparoscopic radical gastrectomy was perform-ed,and the patient was discharged from the hospital 7 d after the surgery.CONCLUSION Asymptomatic intestinal malrotation is best detected by CT,requiring no treatment but possibly interfering with the treatment of other diseases.

关键词： Intestinal malrotation Congenital malformation Gastric cancer Abdominal

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Unconventional Fluorescent and Multi-responsive Polysiloxane:Synthesis,Characterization and Biological Applications

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Chinese Journal of Polymer Science 2024年第5期42卷 579-590,I0006页

作者： Xiao-Di Li Shu-Sheng Li Xu-Bao Jiang Xiao-Li Zhu xiang Zheng kong College of Chemistry and Chemical Engineering University of JinanJinan250022China College of Chemical Engineering Tianjin UniversityTianjin300072China Foshan(Southern China)Institute for New Materials Foshan528200China

Owing to their high significance in fundamental study and diverse applications,stimuli-responsive and fluorescent polymers,particularly those with cluster-triggered emission(CTE)featured by non-conjugated chromophores,have drawn tremendous attention in recent years.In this work,fluorescent and multi-responsive polysiloxane(FRPS)was synthesized by hydrolytic condensation polymerization of 3-aminopropyl methyl diethoxysilane(APMS)with 3-(N-isopropyl propionamide)iminopropyl methyl diethoxysilane(APMS-NIP),which was formed in situ through aza-Michael addition between APMS and N-isopropyl acrylamide.FRPS was not only highly sensitive to temperature,pH and CO_(2) in water,but also showed an enhanced and stimuli-adjustable fluorescence emission.The effects of monomer feeding,pH and CO_(2) on its lower critical solution temperature and fluorescent property were investigated.FRPS fluorescence emission was ascribed to CTE mechanism.In addition,FRPS was shown to be highly potential as physiological indicator for cell imaging,and for controlled release and trace detection of doxorubicin.This study provides therefore a type of stimuli-responsive and fluorescent material for potential applications in biomedical fields,and it is also of great significance for understanding of the fluorescence mechanism of polysiloxane-based stimuli-responsive polymers.

关键词： Polysiloxane Multi-responsiveness Cluster-triggered emission Cell imaging Controlled drug release

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Anchoring heterometallic cluster on P-doped carbon nitride for efficient photocatalytic nitrogen fixation in water and air ambient

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Chinese Chemical Letters 2024年第4期35卷 176-180页

作者： Chao-Long Chen Rong Chen La-Sheng Long Lan-Sun Zheng xiang-Jian kong Collaborative Innovation Center of Chemistry for Energy Materials State Key Laboratory of Physical Chemistry of Solid Surfaces and Department of ChemistryCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China

Light-driven nitrogen fixation to produce ammonia is a green and economical technology of nitrogen reduction but is still quite challenging, especially in an air atmosphere without any sacrificial reagents.Herein, we demonstrate efficient photocatalytic nitrogen fixation using water and air directly by loading lanthanide–transition metal(4f–3d) cluster NdCo_(3) on two-dimensional P-doped graphitic carbon nitrides(PCN) material surface. Benefiting from the increase in the number of nitrogen vacancies(NVs) and highly matched band gap structure and excellent hole trapping ability of clusters, the NdCo_(3)/PCN photocatalyst exhibits efficient nitrogen reduction activity with 371(in air) and 825 μmol h^(-1)g^(-1)(in pure nitrogen)without any sacrificial reagents. The introduction of potassium sulfate inhibits hydrogen production and promotes nitrogen reduction activation. This work suggests that anchoring precisely structured clusters on 2D materials may enhance photocatalytic nitrogen reduction under normal temperature and pressure.

关键词： Photocatalytic Nitrogen fixation 4f-3d Cluster Air atmosphere

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Soil inorganic amendments produce safe rice by reducing the transfer of Cd and increasing key amino acids in brown rice

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Journal of Environmental Sciences 2024年第2期136卷 121-132页

作者： Fanyi kong Shenggao Lu Zhejiang Provincial key Laboratory of Agricultural Resources and Environment Key Laboratory of Environmental Remediation and Ecosystem HealthMinistry of EducationCollege of Environmental and Resource SciencesZhejiang UniversityHangzhou 310058China

The digestibility of cadmium(Cd)in brown rice is directly related to amino acid metabolism in rice and human health.In our field study,three kinds of alkaline calcium-rich soil inorganic amendments(SIAs)at three dosages were applied to produce safe rice and improve the quality of rice in Cd-contaminated paddy.With the increased application of SIA,Cd content in iron plaque on rice root significantly increased,the transfer of Cd from rice root to grain significantly decreased,and then Cd content in brown rice decreased synchronously.The vitro digestibility of Cd in brown rice was estimated by a physiologically based extraction test.Results showed that more than 70%of Cd in brown rice could be digested by simulated gastrointestinal juice.Based on the total and digestible Cd contents in brown rice to evaluate the health risk,the application of 2.25 ton SIA/ha could produce safe rice in acidic slightly Cd-contaminated paddy soils.The amino acids(AAs)in brown rice were determined by high-performance liquid chromatography.The contents of 5 key AAs(KAAs)that actively respond to environmental changes increased significantly with the increased application of SIA.The structural equation model indicated that KAAs could be affected by the Cd translocation capacity from rice root to grain,and consequently altered the ratio of indigestible Cd in brown rice.The formation of indigestible KAAs-Cd complexes by combining KAAs(phenylalanine,leucine,histidine,glutamine,and asparagine)with Cd in brown rice could be considered a potential mechanism for reducing the digestibility of Cd.

关键词： Cadmium digestibility Soil inorganic amendments Safe rice Amino acid Priming effect Health risk

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Dt1 inhibits SWEET-mediated sucrose transport to regulate photoperiod-dependent seed weight in soybean

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Molecular Plant 2024年第3期17卷 496-508页

作者： Xiaoming Li Zhonghui Chen Haiyang Li Lin Yue Cuirong Tan Hongjie Liu Yilong Hu Yuhua Yang Xiani Yao Lingping kong xiang Huangi Bin Yu Chunyu Zhang Yuefeng Guan Baohui Liu Fanjiang kong Xingliang Hou Guangdong Provincial key Laboratory of Applied Botany&State key Laboratory of Plant Diversity and Specialty Crops South China Botanical GardenChinese Academyof SciencesGuangzhou510650China Guangdong Provincial key Laboratory of Plant Adaptation and Molecular Design Guangzhou Key Laboratory of Crop Gene EditingInnovative Center of Molecular Genetics and EvolutionSchool of Life SciencesGuangzhou UniversityGuangzhou 510006China University of Chinese Academy of Sciences Beijing 100049China College of Agronomy and Biotechnology China Agricultural UniversityBeijing 100193China

Soybean is a photoperiod-sensitive short-day crop whose reproductive period and yield are markedly affected by day-length changes.Seed weight is one of the key traits determining the soybean yield;how-ever,the prominent genes that control the final seed weight of soybean and the mechanisms underlying the photoperiod's effect on this trait remain poorly understood.In this study,we identify SwW19 as a major locus controlling soybean seed weight by QTL mapping and determine Dt1,an orthologous gene of Arabidopsis TFL1 that is known to govern the soybean growth habit,as the causal gene of the SW19 locus.We showed that Dt1 is highly expressed in developing seeds and regulates photoperiod-dependent seed weight in soybean.Further analyses revealed that the Dt1 protein physically interacts with the sucrose transporter GmSWEET10a to negatively regulate the import of sucrose from seed coat to the embryo,thus modulating seed weight under long days.However,Dt1 does not function in seed development under short days due to its very low expression.Importantly,we discovered a novel natural allelic variant of Dt1(H4 haplotype)that decouples its pleiotropic effects on seed size and growth habit;i.e.,this variant remains functional in seed development but fails to regulate the stem growth habit of soybean.Collectively,our findings provide new insights into how soybean seed development responds to photoperiod at different latitudes,offering an ideal genetic component for improving soybean's yield by manipulating its seed weightandgrowth habit.

关键词： soybean seed weight photoperiod dt1 sucrose transport

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Temperature prediction model in multiphase flow considering phase transition in the drilling operations

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Petroleum Science 2024年第3期21卷 1969-1979页

作者： Yang Zhang Yong-An Li xiang-Wei kong Hao Liu Teng-Fei Sun College of Mechanical and Electrical Engineering Beijing University of Chemical Technology School of Petroleum Engineering Yangtze University

The study considers gas compression properties, gas slippage, back pressure(BP), phase transition(PT),well depth, and differences in gas-liquid physical properties. A new temperature model for multiphase flow is proposed by considering phase transition in the drilling process. The mathematical model of multiphase flow is solved using the finite difference method with annulus mesh division for grid nodes,and a module for multiphase flow calculation and analysis is developed. Numerical results indicate that the temperature varies along the annulus with the variation of gas influx at the bottom of the well.During the process of controlled pressure drilling, as gas slips along the annulus to the wellhead, its volume continuously expands, leading to an increase in the gas content within the annulus, and consequently, an increase in the pressure drop caused by gas slippage. The temperature increases with the increase in BP and decreases in gas influx rate and wellbore diameter. During gas influx, the thermal conductivity coefficient for the gas-drilling mud two phases is significantly weakened, resulting in a considerable change in temperature along the annulus. In the context of MPD, the method of slightly changing the temperature along the annulus by controlling the back pressure is feasible.

关键词： Managed pressure drilling Phase transition Temperature Gas-drilling mud two phase

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Unconventional Fluorescent and Multi-responsive Polyethyleneimine with LCST and UCST Behavior:Synthesis,Characterization and Biological Applications

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Chinese Journal of Polymer Science 2024年第6期42卷 826-837页

作者： Feng-Ming Yin Li-Li Wu Shu-Sheng Li Xiao-Na Pan Xiao-Li Zhu Xu-Bao Jiang xiang Zheng kong College of Chemistry and Chemical Engineering University of JinanJinan250022China Shandong Institute for Product Quality Inspection Jinan250102China College of Chemical Engineering Tianjin UniversityTianjin300072China

Non-aromatic fluorescent and multi-responsive materials,exhibiting inherent fluorescence emission and controlled phase change,have garnered significant attention in recent years.However,the underlying interaction between their fluorescent properties and phase transition remains unclear.In this study,we synthesized a series of catalyst-free aza-Michael addition-based polyethyleneimine(RFPEI)materials by reacting polyethyleneimine(PEI)with N-isopropyl acrylamide(NIPAM).The resulting RFPEI was comprehensively characterized,and demonstrated dual-phase transition behavior(LCST and UCST)in water,which could be finely tuned by adjusting its composition or external factors such as pH.Notably,upon UV irradiation(365 nm),RFPEI exhibited strong fluorescence emission.We further investigated the effects of NIPAM grafting percentage to PEI,polymer concentration,and pH on the LCST/UCST and fluorescent properties of RFPEI aqueous solutions.Moreover,we showcased the great potential of RFPEI as a versatile tool for physiological cell imaging,trace detection,and controlled release of doxorubicin.Our study presents a novel class of stimuli-responsive fluorescent materials with promising applications in the field of biomedicine.

关键词： Polyethyleneimine Multi-responsiveness Intrinsic fluorescence emission Cell imaging Controlled drug release

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