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Tuning structural,electrical,dielectric and magnetic properties of Mg-Cu-Co ferrites via dysprosium(Dy^(3+))doping

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Journal of Rare Earths 2024年第1期42卷 137-146,I0005页

作者： maria Akhtar M.S.Hasan nasir Amin n.A.Morley Muhammad Imran Arshad Department of Physics Government College UniversityFaisalabad38000Pakistan Department of Physics The University of Lahore53700Pakistan Department of Materials Science and Engineering The University of SheffieldS13JDUK Department of Physics&Astronomy University College LondonUK

In current research work,Dy3+substituted Mg0.5Cu0.25Co0.25Fe2-xDyxO4(0.0≤x≤0.04 with the step interval of 0.01)soft ferrites were synthesized by the sol-gel auto combustion *** prepared samples were characterized by the techniques using X-ray diffraction(XRD),scanning electron microscopy(SEM),energy dispersive X-ray spectroscopy(EDS),Fourier transform infrared(FTIR)spectroscopy,curre nt-voltage(Ⅰ-Ⅴ)measurement,LCR meter,vibrating sample magnetometer(VSM)and *** data reveal that the average crystallite size is 49.71 nm and the lattice constant is 0.83703 nm for sample x=*** non-uniform grain growth was demonstrated by micrographs and impurity-free elemental composition was observed from EDX *** DC resistivity has an increasing and decreasing trend in ferromagnetic and paramagnetic regions with an increase in ***,the high resistivity is observed with the order of 1010Ω·cm,and the activation energy is 0.944 eV for samples x=*** dielectric parameters including dielectric constant,dielectric losses,and impedance gradually decrease with the increase in frequency from 8 Hz to 8 *** minimum dielectric loss at high frequency is found for sample x=*** coercivity(Hc)and saturation magnetization(Ms)are found in the ranges of 520.82-544.02 Oe and 20.5841-21.1473 emu/g,*** observations confirm that dysprosium(x=0.03)doped MCC-soft ferrites may be applicable in transformer cores,microwave absorbance,and telecommunication devices.

关键词： Soft ferrites DC resistivity Dielectric loss Impedance Coercivity Rare earths

Biodegradability of bioplastics in different aquatic environments:A systematic review

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Journal of Environmental Sciences 2024年第8期142卷 169-181页

作者： maria Cristina Lavagnolo Valentina Poli Anna maria Zampini Valentina Grossule Department of Civil Environmental and Architectural Engineering-Laboratory of Environmental EngineeringUniversity of PadovaLungargine Rovetta 8Padova 35100Italy

Bioplastics were first introduced as environmentally friendly materials,with properties similar to those of conventional plastics.A bioplastic is defined as biodegradable if it can be decomposed into carbon dioxide under aerobic degradation,or methane and CO_(2)under anaerobic conditions,inorganic compounds,and new cellular biomass,by the action of naturally occurring *** definition however does not provide any information on the environmental conditions,timescale and extent at which decomposition processes should *** regard to the aquatic environment,recognized standards have been established to assess the ability of plastics to undergo biodegradation;however,these standards fail to provide clear targets to be met to allow labelling of a bioplastic as ***,these standards grant the user an extensive leeway in the choice of process *** these reasons,the comparison of results deriving from different studies is *** authors analysed and discussed the degree of biodegradability of a series of biodegradable bioplastics in aquatic environments(both fresh and salt water)using the results obtained in the laboratory and from on-site testing in the context of different research *** Oxygen Demand(BOD),CO_(2)evolution,surface erosion and weight loss were the main parameters used by researchers to describe the percentage of *** results showed a large variability both in weight loss and BOD,even when evaluating the same type of *** confirms the need for a reference range of values to be established with regard to parameters applied in defining the biodegradability of bioplastics.

关键词： Biodegradation Bioplastic Plastic natural environment Plastic waste

Ion-conducting Membranes Based on Bacterial Cellulose nanofibers Modified by Poly(sodium acrylate-co-2-acrylamido-2-methylpropanesulfonic acid)

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Chinese Journal of Polymer Science 2024年第3期42卷 333-343,I0007页

作者： Elizaveta V.Batishcheva nikolay n.Smirnov natalya V.Bobrova maria P.Sokolova Michael A.Smirnov Institute of Macromolecular Compounds Russian Academy of SciencesBolshoy pr.31Saint Petersburg 199004Russia

Green method for preparation of ion-conducting membranes(ICM) based on bacterial cellulose nanofibers(CnF) modified by a copolymer of sodium acrylate and 2-acrylamido-2-methylpropanesulfonic acid was elaborated. FTIR and nMR data confirmed grafting of polyacrylate onto cellulose surface. Formation of porous structure of the ICM was controlled by SEM and AFM. The maximal ionic conductivity of the membranes reaches 1.5 and 3.1 mS·cm^(-1)(60 ℃ and 98% relative humidity) when they are saturated with water or H_2SO_4(1 mol·L^(-1)) electrolyte,respectively. Prepared ICM was tested as a separator in a symmetrical supercapacitor with electrodes based on polyaniline hydrogel. The assembled cell demonstrate ability to operate at high current density up to 100 A·g^(-1) maintaining specific capacitance 165 F·g^(-1). Maximal specific capacitance of 289 F·g^(-1) was achieved at current density 1 A·g^(-1). Retaining of 90% of initial capacitance after 10000 of charge-discharge cycles proves high electrochemical stability of prepared ICM.

关键词： Bacterial cellulose Ion conductivity Porous membrane Supercapacitor

Carbon sequestration in a bamboo plantation:a case study in a Mediterranean area

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Journal of Forestry Research 2024年第3期35卷 231-238页

作者： Tommaso Chiti Emanuele Blasi maria Vincenza Chiriaco Department for Innovation in Biological Agro-Food and Forest Systems(DIBAF)University of TusciaVia San C.De Lellis snc01100 ViterboItaly Foundation Euro-Mediterranean Center on Climate Change(CMCC) Division on Climate Change Impacts on AgricultureForests and Ecosystem Services(IAFES)Via Garbini5101100 ViterboItaly

In the Mediterranean region,despite bamboo being an alien species that can seriously alter plant and ani-mal biocoenosis,the area occupied by bamboo plantations continues to increase,especially for the purpose to seques-ter carbon(C).However,the C dynamics in the soil-plant system when bamboo is grown outside its native area are poorly *** we investigated the C mitigation potential of the fast-growing Moso bamboo(Phyllostachys edulis)introduced in Italy for climate-change *** analyzed aboveground(AGB)and belowground(as root/shoot ratio)biomass,litter and soil organic C(SOC)at O-15-and 15-30-cm depths in a 4-year-old bamboo plantation in comparison with the former annual cropland on which the bamboo was *** have an idea of the maximum C stored at an ecosystem level,a natural forest adjacent the two sites was also *** the plantation,C accumulation as AGB was stimulated,with 14.8±3.1 Mg C ha^(-1) stored in 3 years;because thinning was done to remove culms from the first year,the mean sequestration rate was 4.9 Mg C ha^(-1) a^(-1).The sequestration rates were high but comparable to other fast-growing tree species in Italy(e.g.,Pinus nigra).SOC was significantly higher in the bamboo plantation than in the cropland only at the 0-15 cm depth,but SOC stock did not *** 4 years were not enough time for a clear increase in SOC,or the high nutrient uptake by bamboos might have depleted the soil nutrients,thus inhibiting the soil organic matter formation by *** comparison,the natural forest had significantly higher C levels in all the *** C dynamics at an ecosystem level,the bamboo plantation on the former annual cropland led to substantial C removal from the atmosphere(about 12 Mg C ha^(-1) a^(-1)).However,despite the promising C sequestration rates by bamboo,its introduction should be carefully considered due to potential ecological problems caused by this species in overexploited environments such as the Med

关键词： Carbon sequestration Climate change mitigation Mediterranean area Moso bamboo Soil organic carbon

Self-healable and Robust Film Based on Electroactive Polymer Brush as Electrode for Flexible Supercapacitor

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Chinese Journal of Polymer Science 2024年第8期42卷 1049-1059页

作者： maria P.Sokolova Vitaly K.Vorobiov nikolay n.Smirnov Ivan S.Kuryndin natalya V.Bobrova Michael A.Smirnov Institute of Macromolecular Compounds Russian Academy of SciencesBolshoy pr.31Saint Petersburg 199004Russia

The aim of this study was to develop self-healable and robust elect roconductive film based on polyaniline copolymer for application as electrode in flexible *** this purpose,the electroconductive polymer brushes(EPB)was *** synthesis of EPB is based on graft polymerizations of acrylamide(AAm)on poly(vinyl alcohol)(PVA)with formation of PVA-PAAm polymer brush and subsequent graft copolymerization of aniline and p-phenylenediamine on PVA-PAAm resulting in formation of EPB with electroconducting copoly(aniline-co-pphenylenediamine)(PAPh DA).It was found that the ratio between PVA and PAAm at the first stage greatly influence the electrochemical performance of the *** films were prepared by casting of EPB solution with subsequent *** of electrical current distribution through the film with AFM reveal more uniform distribution of PAPhDA in EPB in comparison with reference PVA-PAPhDA and PAAm-PAPhDA *** was demonstrated that mechanical cha racteristics and electrical conductivity values of films restore at large extent after curring and self-healing under optimal relative humidity level(58%).The flexile supercapacitor cell with EPB film electrodes demon strate specific capacitance 602 mF·cm^(-2)at the current density of 1 mA·cm^(-2)and retention 94%of initial capacitance after 5000 charge/discharge cycles.

关键词： Polymer brush Polyaniline Flexible supercapacitor Self-healing Electroconducting film

Has the open surgical approach in colorectal cancer really become uncommon?

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World Journal of Gastrointestinal Surgery 2024年第6期16卷 1485-1492页

作者： maria Cariati Giuseppe Brisinda maria Michela Chiarello Department of Surgery Azienda Sanitaria Provinciale di CrotoneCrotone 88900Italy Abdominal and Endocrine Metabolic Medical and Surgical Sciences Fondazione Policlinico Universitario A Gemelli IRCCSRome 00168Italy Department of Surgery Azienda Sanitaria Provinciale di CosenzaCosenza 87100Italy

Colorectal cancer is the third most common cancer in the *** is man-datory to treat patients with colorectal *** colorectal cancer be treated in laparoscopy?Scientific literature has validated the oncological quality of laparo-scopic approach for the treatment of patients with colorectal *** non-inferiority trials with good remote control have answered positively to this long-debated *** as 1994,first publications demonstrated technical feasibility and compliance with oncological imperatives and,as far as short-term outcomes are concerned,there is no difference in terms of mortality and post-operative morbidity between open and minimally invasive surgical approaches,but only longer operating times at the beginning of the ***,from 2007 onwards,long-term results were published that demonstrated the ab-sence of a significant difference regarding overall survival,disease-free survival,quality of life,local and distant recurrence rates between open and minimally in-vasive *** this editorial,we aim to summarize the clinical and technical aspects which,even today,make the use of open surgery relevant and necessary in the treatment of patients with colorectal cancer.

关键词： Colorectal cancer Laparoscopy Laparoscopic colorectal resection Bowel obstruction Bowel perforation Advanced colorectal cancer

History of chronic gastritis:How our perceptions have changed

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World Journal of Gastroenterology 2024年第13期30卷 1851-1858页

作者： Dmitry Bordin maria Livzan Department of Pancreatic Biliary and Upper GI Tract DiseasesA.S.Loginov Moscow Clinical Scientific CenterMoscow 111123Russia Department of Propaedeutic of Internal Diseases and Gastroenterology Russian University of MedicineMoscow 127006Russia Department of Outpatient Therapy and Family Medicine Tver State Medical UniversityTver 170100Russia Department of Internal Medicine and Gastroenterology Omsk State Medical UniversityOmsk 644099Russia

Currently,the diagnostic strategy for chronic gastritis(CG)is aimed not just at fixing the presence of gastric mucosal inflammation,but also at gastric cancer(GC)risk stratification in a particular *** classification approach with the definition of the stage of gastritis determines the need,activities and frequency of dynamic monitoring of a ***,this attitude to the patient suffering from CG was far from *** present publication is a literature review describing the key milestones in the history of CG research,from the description of the first observations of inflammation of the gastric mucosa,assessment of gastritis as a predominantly functional disease,to the advent of endoscopy of the upper digestive tract and diagnostic gastric biopsy,assessment of the role of Helicobacter pylori infection in progression of inflammatory changes to atrophy,intestinal metaplasia,dysplasia and GC.

关键词： Chronic gastritis Intestinal metaplasia Dysplasia Gastric cancer Helicobacter pylori

Kinetic scale magnetic holes in the terrestrial magnetosheath:A review

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Science China Earth Sciences 2024年第9期67卷 2739-2771页

作者： Quanqi SHI Shutao YAO maria HAMRIn Ji LIU Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment Institute of Space SciencesShandong UniversityWeihai 264209China Department of Physics UmeåUniversityUmeå90746Sweden Department of Physics University of AlbertaEdmonton T6K 2P6Canada

Magnetic holes at the ion-to-electron kinetic scale(KSMHs)are one of the extremely small intermittent structures generated in turbulent magnetized *** recent years,the explorations of KSMHs have made substantial strides,driven by the ultra-high-precision observational data gathered from the Magnetospheric Multiscale(MMS)*** review paper summarizes the up-to-date characteristics of the KSMHs observed in Earth’s turbulent magnetosheath,as well as their potential impacts on space *** review starts by introducing the fundamental properties of the KSMHs,including observational features,particle behaviors,scales,geometries,and distributions in terrestrial *** have discovered that KSMHs display a quasi-circular electron vortex-like structure attributed to electron diamagnetic *** electrons exhibit noticeable non-gyrotropy and undergo *** occurrence rate of KSMH in the Earth’s magnetosheath is significantly greater than in the solar wind and magnetotail,suggesting the turbulent magnetosheath is a primary source ***,KSMHs have also been generated in turbulence simulations and successfully reproduced by the kinetic equilibrium ***,KSMHs have demonstrated their ability to accelerate electrons by a novel non-adiabatic electron acceleration mechanism,serve as an additional avenue for energy dissipation during magnetic reconnection,and generate diverse wave phenomena,including whistler waves,electrostatic solitary waves,and electron cyclotron waves in space *** results highlight the magnetic hole’s impact such as wave-particle interaction,energy cascade/dissipation,and particle acceleration/heating in space *** end this paper by summarizing these discoveries,discussing the generation mechanism,similar structures,and observations in the Earth’s magnetotail and solar wind,and presenting a future extension perspective in this active field.

关键词： Magnetic hole Magnetic dip/cavity Electron vortex Magnetosheath Turbulence Coherent structure Mirror mode Kinetic scale Electron acceleration Whistler

Co-Optimization of Behind-the-Meter and Front-of-Meter Value Streams in Community Batteries

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Journal of Modern Power Systems and Clean Energy 2024年第2期12卷 334-345页

作者： Carmen Bas Domenech Antonella maria De Corato Pierluigi Mancarella University of Melbourne Parkville 2010VictoriaAustralia Department of Electrical and Electronic Engineering The University of ManchesterManchesterU.K. IEEE

Community batteries(CBs)are emerging to support and even enable energy communities and generally help consumers,especially space-constrained ones,to access potential techno-economic benefits from storage and support local grid ***,the economic viability of CB projects is often *** this regard,typical feasibility studies assess CB value for behind-the-meter(BTM)operation or whole-sale market participation,i.e.,front-of-meter(FOM).This work proposes a novel techno-economic operational framework that allows systematic assessment of the different options and introduces a two-meter architecture that co-optimizes both BTM and FOM benefits.A real CB project application in Australia is used to demonstrate the significant two-meter co-optimization opportunities that could enhance the business case of CB and energy communities by multi-service provision and value stacking.

关键词： Behind-the-meter community battery distributed energy resource(DER) energy community front-of-meter value stacking