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Journal of Rare Earths 2018年第1期36卷 1-41页

作者： Jean-Claude g.Bünzli ka-Leung Wong Institute of Chemical Sciences and Engineering Swiss Federal Institute of Technology Lausanne (EPFL) CH-1015 Lausanne Switzerland Department of Chemistry Hong Kong Baptist University Kowloon Tong Hong Kong China

Mechanoluminescence （ML） is the emission of light consecutive to a mechanical force or stress imposed to a crystalline material. Many inorganic and organic compounds present this phenomenon that is known for over 400 years. Lanthanide and uranyl salts were among the first substances investigated for this property. Mechanoluminescence, also referred to as triboluminescence, is often considered as being a badly understood phenomenon. In fact it is because of two main reasons. Firstly, a variety of different mechanical stresses, from simple rubbing, to applied pressure, crushing, impact of a weight, ultrasound, laser-generated shock wave, crystallization, dissolution of crystals, or even wind can trigger it. Secondly, ML is very sensitive to the purity and morphology of the sample： in inorganic compounds, generation of traps by doping ＂impurities＂（e.g. lanthanide ions） is responsible for light emission so that the exact composition of the sample has to be known to a very detailed level; for chelates, the crystallization conditions are crucial since they often generate extended networks of weak interactions that are instrumental in triggering ML when they are broken. In fact mechanisms of ML are relatively well known and theories and models often reproduce very well the experiments. Additionally, practical applications are at hand, for example stress, crack, and impact sensors based on SrAI204：Eu11 or Et3NH[Eu（dbm）4] are used to test structures and materials as diverse as road bridges, reinforced concrete elements, pressur- ized containers or airplane wings and to image the propagation of cracks or stress distribution. Military and security applications involve detecting the passage of vehicle or soldiers and producing counter- feiting inks while more joyful applications are luminous balls, wrapping papers and adhesive tapes. Not only bulk materials, but micro- and nanoparticles feature mechanoluminescent properties and single particle manipulation under an AFM allows

关键词： MechanoluminescenceRare earthsStress sensorsPressure sensorsImpact sensors

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Novel Approaches of Using of Spirulina Platensis in Natural Rubber Based Composites

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Journal of Renewable Materials 2018年第7期6卷 680-687页

作者： Ewa głowińska Janusz Datta Paulina Parcheta and Natalia kaźmierczak Department of Polymers Technology Gdańsk University of TechnologyNarutowicza Street 11/1280-233 GdańskPoland

The aim of this work was to investigate the influence of Spirulina (Spirulina platensis) as a natural filler on thecuring characterization, morphology and mechanical, thermomechanical and thermal properties of naturalrubber (NR) based composites. Spirulina was introduced into NR mixture in amount of 0 phr, 10 phr and 30 *** vulcanization process was carried out at the determined process condition by using hydraulic press atoptimum vulcanization time (t90). It was noticed that Spirulina affected on the reduction of t90, and scorch time(t2) of the NR mixtures. Obtained vulcanizates were subjected to the number of tests e.g. scanning electronmicroscopy analysis, mechanical dynamical analysis, tensile test, hardness, and thermogravimetry. generally, itwas found that Spirulina added in amount of 10 phr NR positively influenced on tensile strength (TSb), storagemodulus and hardness of obtained composites.

关键词： Spirulina algae natural rubber composites DMA

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Advantageous mechanochemical synthesis of copper(Ⅰ)selenide semiconductor,characterization,and properties

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Frontiers of Chemical Science and Engineering 2022年第3期16卷 433-442页

作者： katarína gáborová Marcela Achimovičová Michal Hegedüs Vladimír girman Mária kaňuchová Erika Dutková Institute of geotechnics Slovak Academy of SciencesKošice04001Slovakia Institute of Metallurgy Faculty of MaterialsMetallurgy and RecyclingTechnical UniversityKošice04201Slovakia Synthon s.r.o.Blansko67801Czech Republic Faculty of Science Pavol JozefŠafárik UniversityKošice04154Slovakia Institute of Earth Resources Faculty of MiningEcologyProcess Control and GeotechnologiesTechnical UniversityKošice04200Slovakia

Copper(I)selenide-nanocrystalline semiconductor was synthesized via one-step mechanochemical synthesis after 5 min milling in a planetary ball *** kinetics of synthesis was followed by X-ray powder diffraction analysis and specific surface area measurements of milled 2Cu/Se *** X-ray diffraction confirmed the orthorhombic crystal structure of Cu_(2)Se with the crystallite size∼25 *** surface chemical structure was studied by X-ray photoelectron spectroscopy,whereby the binding energy of the Cu 2p and Se 3d signals corresponded to Cu^(+)and Se^(2−)oxidation *** electron microscopy revealed agglomerated nanocrystals and confirmed their orthorhombic structure,as *** optical properties were studied utilizing ultraviolet-visible spectroscopy and photoluminescence *** direct bandgap energy 3.7 eV indicated a blue-shift phenomenon due to the quantum size *** type of Cu_(2)Se synthesis can be easily adapted to production dimensions using an industrial vibratory *** advantages of mechanochemical synthesis represent the potential for inexpensive,environmentally-friendly,and waste-free manufacturing of Cu_(2)Se.

关键词： Cu_(2)Se berzelianite nanocrystalline semiconductor mechanochemical synthesis planetary ball mill

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Investigation of effects of Cocamide Diethanolamide chemical on physical and rheological properties of bituminous binder

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Frontiers of Structural and Civil Engineering 2022年第1期16卷 99-116页

作者： gizem kaCAROgLU Mehmet SALTAN Department of Civil Engineering Suleyman Demirel UniversityIsparta 32200Turkey

In this study,bituminous binder was modified with Cocamide Diethanolamide chemical,a non-ionic surfactant,and the physical and rheological properties of modified binders were *** addition,Cocamide Diethanolamide has been used for the first time to modify bituminous binder,and this situation makes the study *** binder was modified more than once with the chemical by changing modification parameters and using certain additive ratios(1%,3%,and 5%).The effects of different modification parameters and chemical additive on modified samples were investigated with conventional bitumen tests(softening point,penetration,ductility)and Superpave tests(rotational viscometer,rolling thin film oven test,pressure aging vessel,dynamic shear rheometer,bending beam rheometer).In addition,the structural characteristics of the reference binder and modified samples were examined by X-ray diffraction,Fourier Transform Infrared Spectroscopy,scanning electron microscopy,and energy dispersive X-ray *** examinations showed that Cocamide Diethanolamide softens bituminous binder and lowers processing *** addition,compared to reference binder,rutting resistances of modified bituminous binders decreased with the increase of additive ***,modification with Cocamide Diethanolamide increased the resistance to fatigue cracks and thermal cracks.

关键词： Cocamide Diethanolamide bitumen modification rheology Superpave tests

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Oxidative stress and lipid peroxidation products:effect of pinealectomy or exogenous melatonin injections on biomarkers of tissue damage during acute pancreatitis

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Hepatobiliary & Pancreatic Diseases International 2010年第1期9卷 78-82页

作者： Cavit l kahraman Dinler O■uz Hasdemir Oktay Büyüka■ik güler Bu■dayci Department of general Surgery Abant Izzet Baysal University Medical School Department of Biochemistry Abant Izzet Baysal University Medical School

BACKgROUND:Melatonin (N-acetyl-5-methoxytripta-mine) is a free radical scavenger and a strong antioxidant,secreted by the pineal *** this study,we evaluated the effects of decreasing and increasing serum melatonin levels on malonyldialdehyde (MDA),superoxide dismutase (SOD),and reduced glutathione (gSH) levels in pancreatic tissue from rats with experimental acute ***:Experimental acute pancreatitis was induced in three groups of Wistar albino rats (10 animals per group) by pancreatic ductal *** first group had only acute pancreatitis and served as the *** pinealectomy was added to acute pancreatitis in the second group,removing the source of endogenous melatonin (low melatonin levels group).The third group was given 0.1 ml daily intraperitoneal injections of 20 mg/ml melatonin solution for one week (high melatonin levels group).The effects of melatonin levels were evaluated by comparison of the levels of MDA,SOD,and gS in pancreatic ***:We found that intraperitoneal melatonin injections decreased the levels of MDA and increased the levels of SOD and gSH in pancreatic ***:Exogenous melatonin has a preventive effect on lipid peroxidation and oxidative damage in acute pancreatitis.

关键词： pineal gland acute pancreatitis melatonin oxidative damage

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Insulin is necessary for the hypertrophic effect of cholecystokinin-octapeptide following acute necrotizing experimental pancreatitis

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World Journal of gastroenterology 2004年第15期10卷 2275-2277页

作者： Péter Hegyi Zoltán RakonczayJr Réka Sári László Czakó Norbert Farkas Csaba góg József Németh János Lonovics Tamás Takács First Department of Medicine Faculty of MedicineUniversity of Szeged Szeged H6722Hungary School of Cell and Molecular BiosciencesMedical SchoolUniversity of NewcastleNewcastle upon TyneNE2 4HHUnited Kingdom First Department of Medicine Faculty of MedicineUniversity of Szeged Szeged H6722Hungary Jr.School of Cell and Molecular BiosciencesMedical SchoolUniversity of NewcastleNewcastle upon TyneNE2 4HHUnited Kingdom First Department of Medicine Faculty of MedicineUniversity of Szeged Szeged H6722Hungary

AIM:In previous experiments we have demonstrated that by administering low doses of cholecystokinin-octapeptide (CCK-8),the process of regeneration following L-arginine (Arg)-induced pancreatitis is *** rats that were also diabetic(induced by streptozotocin,STZ),pancreatic regeneration was not *** aim of this study was to deduce whether the administration of exogenous insulin could in fact restore the hypertrophic effect of CCK-8 in diabetic-pancreatitic rats. METHODS:Male Wistar rats were used for the experiments. Diabetes mellitus was induced by administering 60mg/kg body mass of STZ intraperitoneally(i.p.),then,on d 8, pancreatitis was induced by 200mg/100 g body mass Arg *** at an interval of 1 *** animals were injected subcutaneously twice daily(at 7 *** 7 p.m.)with 1 μg/kg of CCK-8 and/or 2 IU mixed insulin(300g/L short- action and 700g/L intermediate-action insulin) for 14 d after pancreatitis *** this the animals were killed and the serum amylase,glucose and insulin levels as well as the plasma glucagon levels,the pancreatic mass/body mass ratio(pm/bm),the pancreatic contents of DNA,protein,amylase,lipase and trypsinogen were *** tissue samples were examined by light microscopy on paraffin-embedded sections. RESULTS:In the diabetic-pancreatitic rats treatment with insulin and CCK-8 significantly elevated pw/bm and the pancreatic contents of protein,amylase and lipase vs the rats receiving only CCK-8 ***-8 administered in combination with insulin also elevated the number of acinar cells with mitotic activities,whereas CCK-8 alone had no effect on laboratory parameters or the mitotic activities in diabetic-pancreatitic rats. CONCLUSION:Despite the hypertrophic effect of CCK-8 being absent following acute pancreatitis in diabetic-rats, the simultaneous administration of exogenous insulin restored this *** results clearly demonstrate that insulin is necessary for the hypertrophic ef

关键词： Animals Diabetes Mellitus, Experimental Hypoglycemic Agents Insulin Male Pancreatitis, Acute Necrotizing Rats Rats, Wistar Regeneration Research Support, Non-U.S. gov't Sincalide

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Tumor necrosis factor-α-induced protein 1 and immunity to hepatitis B virus

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World Journal of gastroenterology 2005年第48期11卷 7564-7568页

作者： Marie C Lin Nikki P Lee Ning Zheng Pai-Hao Yang Oscar g Wong Hsiang-Fu Kung Chee-Kin Hui John M Luk george ka-Kit Lau Institute of Molecular Biology The University of Hong KongHong Kong SAR China Department of Surgery The University of Hong Kong Hong Kong SAR China Center for the Study of Liver Diseases The University of Hong Kong Hong Kong SAR China Department of Medicine The University of Hong Kong Hong Kong SAR China

AIM: To compare the gene expression profile in a pair of HBV-infected ***: The gene expression profile was compared in a pair of HBV-infected ***: The twins displayed different disease outcomes. One acquired natural immunity against HBV,whereas the other became a chronic HBV carrier. Eightyeight and forty-six genes were found to be up- or downregulated in their PBMCs, respectively. Tumor necrosis factor-alpha-induced protein 1 (TNF-αIP1) that expressed at a higher level in the HBV-immune twins was identified and four pairs of siblings with HBV immunity by RTPCR. However, upon HBV core antigen stimulation,TNF-αIP1 was downregulated in PBMCs from subjects with immunity, whereas it was slightly upregulated in HBV carriers. Bioinformatics analysis revealed a K+channel tetramerization domain in TNF-αIP1 that shares a significant homology with some human, mouse, and C elegan ***: TNF-αIP1 may play a role in the innate immunity against HBV.

关键词： TNF-α HBV Immunity

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ERROR ESTIMATES FOR THE TIME DISCRETIZATION FOR NONLINEAR MAXWELL'S EQUATIONS

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Journal of Computational Mathematics 2008年第5期26卷 677-688页

作者： Mavián Slodika Ján Bua Jr. Department of Mathematical Analysis Ghent University

This paper is devoted to the study of a nonlinear evolution eddy current model of the type δtB（H）＋ △↓× （ △↓ × H） =0 subject to homogeneous Dirichlet boundary conditions H × v = 0 and a given initial datum. Here, the magnetic properties of a soft ferromagnet are linked by a nonlinear material law described by B（H）. We apply the backward Euler method for the time discretization and we derive the error estimates in suitable function spaces. The results depend on the nonlinearity of B（H）.

关键词： Electromagnetic field Nonlinear eddy current problem Time discretization,Error estimate.

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Epidemiologic characteristics of Helicobacter pylori infection in southeast Hungary

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World Journal of gastroenterology 2019年第42期25卷 6365-6372页

作者： Lenke Bálint Andrea Tiszai gábor Kozák Ilona Dóczi Veronika Szekeres Orsolya Inczefi georgina Ollé Krisztina Helle Richárd Róka András Rosztóczy Division of gastroenterology First Department of MedicineUniversity of SzegedSzeged 6720Hungary Department of Physiology University of SzegedSzeged 6720Hungary of Clinical Microbiology University of SzegedSzeged 6725Hungary Hungarian National Blood Transfusion Service Szeged 6722Hungary

BACKgROUND Epidemiologic studies have revealed a decrease in the prevalence of Helicobacter pylori(***)infection in Western *** To obtain data regarding the prevalence of *** in Csongrád and Békés Counties in Hungary,evaluate the differences in its prevalence between urban and rural areas,and establish factors associated with positive *** One-thousand and one healthy blood donors[male/female:501/500,mean age:40(19–65)years]were enrolled in this *** were tested for *** Igg antibody positivity via enzyme-linked immunosorbent *** analysis by age,gender,smoking habits,alcohol consumption,and urban vs nonurban residence was also *** The overall seropositivity of *** was 32%.It was higher in males(34.93%vs 29.2%,P=0.0521)and in rural areas(36.2%vs 27.94%,P=0.0051).Agricultural/industrial workers were more likely to be positive for infection than office workers(38.35%vs 30.11%,P=0.0095)and rural subjects in Békés County than those in Csongrád County(43.36%vs 33.33%,P=0.0015).CONCLUSION Although the prevalence of *** infection decreased in recent decades in Southeast Hungary,it remains high in middle-aged rural *** accepted risk factors for *** positivity appeared to be valid for the studied population.

关键词： Helicobacter pylori Epidemiology Prevalence Central Europe Healthy volunteers Enzyme-linked immunosorbent assay Differences in urban and rural population

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The effect of severe plastic deformation on the Mg properties after CEC deformation

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Journal of Magnesium and Alloys 2020年第3期8卷 761-768页

作者： B.Suikowski M.Janoska.g.Boczkal R.Chulist M.Mroczkowski P.Paika Department of Non-Ferrous Metals Engineering Faculty of Non-Ferrous MetalsAGH University of Science and Technology30 Mickiewicza Av.Krakow 30-059Poland Institute of Metallurgy and Materials Science Polish Academy of Sciences25 Reymonta St.Krakow 30-059Poland

In this study,the effect of severe plastic deformation on the Mg grain refinement and recovery mechanism was *** pure magnesium was deformed at room temperature by cycling extrusion-compression(CEC)process up to large *** steps of deformation have been used by applying 1,2 and 4 passes of CEC giving a total effective plastic strain ofε=*** and structural properties of Mg in initial state and the states after successive steps of deformation were *** mechanical properties were determined by microhardness and compression tests at room *** structural investigations involved light microscope observations,electron back scattered diffraction and texture measurements by X-ray *** was found that the CEC process refines the grain size down to 6.4μm and reduces strong rolling texture ***,only the first two passes had a strong effect on mechanical properties while a larger number of CEC cycles(above 4)led to failure of the samples with a small effect on *** observation correlates with texture evolution indicating a more random orientation distribution that slows down the typical for hep metals rapid work *** was found that the CEC process activated twin dynamic recrystallization in deformed *** process led to the formation of new randomly oriented grains inside the twinned areas and as a consequence it reduced the strong rolling texture components.

关键词： Magnesium Cyclic extrusion compression Texture Microhardness

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