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Mapping multiple phases in curcumin binary solid dispersions by fluorescence contrasting

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Chinese Chemical Letters 2024年第9期35卷 266-272页

作者： Ying xu Chengying Shen Hailong Yuan wei Wu Key Laboratory of Smart Drug Delivery of MOE School of PharmacyFudan UniversityShanghai 201203China Center for Medical Research and Innovation Shanghai Pudong HospitalFudan University Pudong Medical CenterShanghai 201399China Department of Pharmacy Air Force Medical CenterPLABeijing 100142China Jiangxi Provincial People’s Hospital The First Affiliated Hospital of Nanchang Medical CollegeNanchang 330006China

The microphases and miscibility in binary curcumin(Cur)solid dispersions(SDs)with amorphous polyvinylpyrrolidone K30(PVP K30)and semi-crystalline poloxamer(P407)and poly(ethylene glycol)6000(PEG6000)as carriers were investigated by fluorescence contrasting utilizing confocal laser scanning microscopy.A super sensitive fluorophore P4 with typical aggregation-caused quenching properties was employed to stain the continuous polymer phases and contrasted with the autofluorescence of the model drug *** addition,differential scanning calorimetry(DSC)and powder X-ray diffraction(PXRD)were utilized to assist in explanation of the fluorescence *** all three SD systems,there is always a homogenous polymer phase stained by P4 and it is difficult to adulterate Cur crystals by ***-enriched rather than polymer-enriched domains could be *** the Cur-PVP K30 system,Cur exists in an amorphous form at a Cur loading level of 50%and below,while Cur crystallines phase out and continuously grow with the increase of Cur loading from 60%to 90%.The phase behaviors in the Cur-P407 and Cur-PEG 6000 systems are similar but with minor *** both systems,Cur phases out as clusters of drug-enriched domains at a loading level of 20%and below,which however cannot be correlated with crystallization,as evidenced by both DSC and *** is a transition from an amorphous to a crystalline state from 20%to 30%Cur loading,above which Cur crystallines can be *** is interesting that a co-mix phase of both Cur-and PEG 6000-enriched domains can be identified at Cur loading levels of 10%and *** together,it is concluded that contrasting Cur autofluorescence with the signals of P4 proves to be a functional strategy to reveal multiple phases in the binary SD systems investigated.

关键词： Solid dispersion Curcumin PEG PVP Poloxamer Fluorescence Environment-responsive Confocal laser scanning microscopy

Sequence [2,3]-Sigmatropic Rearrangement: One-Pot Synthesis of Proparggyl Allenylamines

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Chinese Journal of Chemistry 2024年第18期42卷 2223-2227页

作者： Huihui feng Yujuan Xie Lliang Huang Yongqing xu Junhai Huang Huangdi feng College of Chemistry and Chemical Engineering Shanghai University of Engineering ScienceShanghai 201620China Shanghai Frontiers Science Research Centerfor Druggability of Cardiovascular noncoding RNA Institute for Frontier Medical Technology Shanghai Universityof Engineering ScienceShanghai 201620China

Allenes,served as highly sought-after building blocks,are an indispensable component of synthetic *** utility in modulating the chemical,physical,and pharmaceutical properties of organic compounds make allenes a desirable choice in various ***,we report a facile method for the atom-economical synthesis of propargyl allenylamines via an underdeveloped[2,3]-sigmatropic *** strategy employs easily accessible propargylamines as starting materials,which are first converted into propargyl ammonium salts,followed by a base-promoted[2,3]-sigmatropic *** one-pot,two-step reaction proceeds in the absence of transition metals,displays a very broad scope,and does not require the introduction of the electron-withdrawing group into the starting materials.

关键词： Allene Propargylamine C-N activation Sigmatropic rearrangement Metal-free Synthetic methods Domino reactions

Multiple damage zones around hydraulic fractures generated by high-frequency pulsating hydraulic fracturing

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Petroleum Science 2024年第4期21卷 2688-2702页

作者： Yan Peng Sheng-Jie wei Guang-Qing Zhang Da-wei Zhou Chuang-Chao xu School of Petroleum Engineering China University of Petroleum PetroChina Changqing Oilfield Company

Pulsating hydraulic fracturing(PHF) is a promising fracturing method and can generate a dynamic periodic pressure. The periodic pressure can induce fatigue failure of rocks and decrease initiation pressure of fracture. If the frequency of periodic pressure exceeds 10 Hz, the distribution of pressure along the main fracture will be heterogeneous, which is much different from the one induced by the common fracturing method. In this study, the impact of this special spatial feature of pressure on hydraulic fracture is mainly investigated. A coupled numerical simulation model is first proposed and verified through experimental and theoretical solutions. The mechanism of secondary fracture initiation around the main fracture is then discovered. In addition, sensitivity studies are conducted to find out the application potential of this new method. The results show that(1) this coupled numerical simulation model is accurate. Through comparison with experimental and theoretical data, the average error of this coupled model is less than 1.01%.(2) Even if a reservoir has no natural fracture, this heterogeneous distribution pressure can also cause many secondary fractures around the main fracture.(3) The mechanism of secondary fracture initiation is that this heterogeneous distribution pressure causes tensile stress at many locations along the main fracture.(4) Through adjusting the stimulation parameters, the stimulation efficiency can be improved. The average and amplitude of pressure can increase possibility of secondary fracture initiation. The frequency of this periodic pressure can increase number of secondary fractures. Even 6 secondary fractures along a 100 m-length main fracture can be generated.(5) The influence magnitudes of stimulation parameters are larger than ones of geomechanical properties, therefore, this new fracturing method has a wide application potential.

关键词： Tight reservoir Reservoir stimulation Numerical simulation Secondary fracture Fracture initiation

Colloid-facilitated release of polybrominated diphenyl ethers at an e-waste recycling site: evidence from undisturbed soil core leaching experiments

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Frontiers of Environmental Science & Engineering 2024年第2期18卷 91-101页

作者： Zebin Huo Mengjun Xi Lianrui xu Chuanjia Jiang wei Chen College of Environmental Science and Engineering Ministry of Education Key Laboratory of Pollution Processes and Environmental CriteriaTianjin Key Laboratory of Environmental Remediation and Pollution ControlNankai UniversityTianjin 300350China

Polybrominated diphenyl ethers (PBDEs), a class of persistent organic pollutants, have been frequently detected in soil at e-waste recycling sites. However, the key factors controlling the transport of PBDEs from surface soil to the vadose zone and groundwater are unclear. Here, colloid-enhanced leaching of PBDEs from undisturbed soil cores collected at an e-waste recycling site in Tianjin, China, is reported. Spatially heterogeneous release of colloids and PBDEs was observed in all the tested soil cores under chemical and hydrodynamic perturbations, indicating the presence of preferential flow paths. Colloid concentration in the effluent significantly increased as ionic strength decreased (from 10 to 0.01 mmol/L), probably due to the stronger electrostatic repulsion between colloidal particles and the soil matrix at lower ionic strength. In contrast, colloid mobilization was not significantly affected by the changes in pH of the influent (from 4.0 to 10.0) and flow rate (from a Darcy velocity of 1.5 to 6.0 cm/h). The concentrations of 2,2′,3,3′,4,4′,5,5′,6,6′-decabromodiphenyl ether (BDE-209), the predominant PBDE congener at the site, detected in the leachate (ranging from 1.09 to 3.43 ng/L) were much lower than previously reported results from packed column leaching tests, and were positively correlated with colloid concentrations. This indicates that remobilization of colloids at e-waste recycling sites can promote the leaching and downward migration of PBDEs from surface soil. The findings highlight the potential risk of surface soil PBDE contamination to groundwater quality and call for further understanding of colloid-facilitated transport for predicting the fate of PBDEs at e-waste recycling sites.

关键词： Polybrominated diphenyl ether Colloid-facilitated transport E-waste recycling site Undisturbed soil core Groundwater quality

Theory and test of underground explosions:Coupling rule between cratering and ground shock

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Underground Space 2024年第4期17卷 146-160页

作者： wei Guo Jie Li Benjun Shi Tianhan xu Xiaohui xu Gan Li Jie Shi State Key Laboratory of Disaster Prevention and Mitigation of Explosion and Impact Army Engineering University of PLANanjing 210007China

Calculating the parameters of the ground shock induced by an underground explosion is a complex energy coupling *** is difficult to establish a unified ground shock coupling law from limited test *** paper summarizes the research results obtained at home and abroad and systematically analyzes the coupling mechanism of craters formed by an underground explosion and the ground *** differences between the concepts of"closed-explosion critical depth"and"equivalent closed-explosion critical depth"are clearly *** spreading of the ground shock energy is attributed to the explosive expansion of the air cavity,revealing a linear relationship between the volume of the cavity region(or the volume of the crack region)and the ground shock energy associated with the underground *** proportionality factor is related to the mechanical properties of the medium and is independent of the magnitude of the explosion *** on this,a theoretical calculation formula and conversion method for the ground shock coupling coefficient were *** tests were conducted in clay and Plexiglass under varying burial *** test results were consistent with the theoretically calculated *** study provides a theoretical basis for the design of explosion-resistant structures in underground engineering.

关键词： Underground explosion Ground shock coupling Coupling coefficient Equivalent closed explosion Experimental study

Comparison of microwave- and thermal-assisted rock fragmentation methods at different temperatures and loading rates

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International Journal of Mining Science and Technology 2024年第6期34卷 799-819页

作者： wei Yao Shuai Wang Bangbiao Wu Ying xu Kaiwen Xia State Key Laboratory of Hydraulic Engineering Intelligent Construction and Operation School of Civil EngineeringTianjin UniversityTianjin 300072China China Railway Design Corporation Tianjin 300308China Institute of Geosafety School of Engineering and TechnologyChina University of GeosciencesBeijing 100083China

Understanding the effects of microwave irradiation and thermal treatment on the dynamic compression and fragmentation properties of rocks is essential to quantify energy consumption in rock *** this study,Fangshan granite(FG)specimens were exposed to microwave irradiation and heat *** damage of FG specimens induced by these two methods was compared using X-ray CT scanning and ultrasonic wave *** temperatures of FG after microwave irradiation and thermal treatment were effectively evaluated using a newly proposed technique.A novelty method for precisely determining the geometric features of fragments is developed to estimate the fragmentation ***,the dynamic uniaxial compressive strength(UCS),the dynamic fragmentation characteristics,and the fragmentation energy of FG after these two pretreatment methods can be reasonably *** noticeable distinction of loading rate effect on the dynamic UCS of FG between these two pretreatment methods is first observed.A relationship is established between the dynamic UCS and the damage induced by microwave irradiation and heat ***,fragmentation energy fan analysis is introduced to accurately compare the fragmentation properties of FG after two pretreatment methods in dynamic compression tests.

关键词： Fangshan granite Dynamic experiments Microwave irradiation Thermal treatment Loading rate Fragmentation

Coordinated Dispatch Based on Distributed Robust Optimization for Interconnected Urban Integrated Energy and Transmission Systems

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Journal of Modern Power Systems and Clean Energy 2024年第3期12卷 840-851页

作者： wei xu Yufeng Guo Tianhui Meng Yingwei Wang Jilai Yu the School of Electrical Engineering and Automation Harbin Institute of TechnologyHarbin 150001China

To improve the economic efficiency of urban integrated energy systems(UIESs)and mitigate day-ahead dispatch uncertainty,this paper presents an interconnected UIES and transmission system(TS)model based on distributed robust ***,interconnections are established between a TS and multiple UIESs,as well as among different UIESs,each incorporating multiple energy *** Bregman alternating direction method with multipliers(BADMM)is then applied to multi-block problems,ensuring the privacy of each energy system operator(ESO).Second,robust optimization based on wind probability distribution information is implemented for each ESO to address dispatch *** column and constraint generation(C&CG)algorithm is then employed to solve the robust ***,to tackle the convergence and practicability issues overlooked in the existing studies,an external C&CG with an internal BADMM and corresponding acceleration strategy is ***,numerical results demonstrate that the adoption of the proposed model and method for absorbing wind power and managing its uncertainty results in economic benefits.

关键词： Distributed robust optimization distributionally robust dispatch urban integrated energy system transmission system external column and constraint generation(C&CG) internal Bregman alternating direction method with multipliers(BADMM)

Ferroptosis and endoplasmic reticulum stress in ischemic stroke

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Neural Regeneration Research 2024年第3期19卷 611-618页

作者： Yina Li Mingyang Li Shi feng Qingxue xu xu Zhang Xiaoxing Xiong Lijuan Gu Central Laboratory Renmin Hospital of Wuhan UniversityWuhanHubei ProvinceChina Department of Anesthesiology Renmin Hospital of Wuhan UniversityWuhanHubei ProvinceChina Department of Neurosurgery Renmin Hospital of Wuhan UniversityWuhanHubei ProvinceChina

Ferroptosis is a form of non-apoptotic programmed cell death,and its mechanisms mainly involve the accumulation of lipid peroxides,imbalance in the amino acid antioxidant system,and disordered iron *** primary organelle responsible for coordinating external challenges and internal cell demands is the endoplasmic reticulum,and the progression of inflammatory diseases can trigger endoplasmic reticulum *** has suggested that ferroptosis may share pathways or interact with endoplasmic reticulum stress in many diseases and plays a role in cell *** and endoplasmic reticulum stress may occur after ischemic ***,there are few reports on the interactions of ferroptosis and endoplasmic reticulum stress with ischemic *** review summarized the recent research on the relationships between ferroptosis and endoplasmic reticulum stress and ischemic stroke,aiming to provide a reference for developing treatments for ischemic stroke.

关键词： cell death endoplasmic reticulum stress ferroptosis ischemic stroke lipid peroxidation

Intravitreal conbercept injection with panretinal photocoagulation for high-risk proliferative diabetic retinopathy with vitreous hemorrhage

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International Journal of Ophthalmology(English edition) 2024年第6期17卷 1066-1072页

作者： Yao xu Qing Ye wei Shen Department of Ophthalmology the Fourth Affiliated Hospital of Soochow UniversitySuzhou 215000Jiangsu ProvinceChina Department of Ophthalmology Suzhou Kowloon HospitalShanghai Jiao Tong University School of MedcineSuzhou 215000Jiangsu ProvinceChina Department of Ophthalmology the First Affiliated Hospital of Soochow UniversitySuzhou 215000Jiangsu ProvinceChina

AIM:To assess the clinical efficacy and safety of combining panretinal photocoagulation(PRP)with intravitreal conbercept(IVC)injections for patients with high-risk proliferative diabetic retinopathy(HR-PDR)complicated by mild or moderate vitreous hemorrhage(VH),with or without diabetic macular edema(DME).METHODS:Patients diagnosed with VH with/without DME secondary to HR-PDR and received PRP combined with IVC injections were recruited in this retrospective *** establishing the patient’s diagnosis,an initial IVC was performed,followed by prompt administration of *** cases who significant bleeding persisted and impeded the laser operation,IVC was sustained before supplementing with *** the completion of PRP,patients were meticulously monitored for a minimum of six *** therapy and IVC injections were judiciously adjusted based on fundus fluorescein angiography(FFA)*** effect and the incidence of adverse events were ***:Out of 42 patients(74 eyes),29 were male and 13 were female,with a mean age of 59.17±12.74y(33-84y).The diabetic history was between 1wk and 26y,and the interval between the onset of visual symptoms and diagnosis of HR-PDR was *** affected eye received 2.59±1.87(1-10)IVC injections and underwent 5.5±1.02(4-8)sessions of *** these,68 eyes received PRP following 1 IVC injection,5 eyes after 2 IVC injections,and 1 eye after 3 IVC *** absorption of VH was observed in all 74 eyes 5-50wk after initial treatment,with resolution of DME in 51 eyes 3-48wk after initial treatment.A newly developed epiretinal membrane was noted in one *** acuity significantly improved in 25 *** complications such as glaucoma,retinal detachment,or endophthalmitis were ***:The study suggests that the combination of PRP with IVC injections is an effective and safe modality for treating diabetic VH in patients with HR-PDR.

关键词： conbercept panretinal photocoagulation high-risk proliferative diabetic retinopathy vitreous hemorrhage