检索结果-南通市图书馆

Review on friction stir welding of dissimilar magnesium and aluminum alloys: Scientometric analysis and strategies for achieving high-quality joints

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Magnesium and Alloys 2023年第11期11卷 4082-4127页

作者： Mohamed M.Z.Ahmed Mohamed M.El-Sayed Seleman dariusz Fydrych Gürel ÇAM Department of Mechanical Engineering College of Engineering at Al KharjPrince Sattam Bin Abdulaziz UniversityAl Kharj 11942Saudi Arabia Department of Metallurgical and Materials Engineering Faculty of Petroleum and Mining EngineeringSuez UniversitySuez 43512Egypt Faculty of Mechanical Engineering and Ship Technology Institute of Machines and Materials TechnologyGdańsk University of TechnologyGabriela Narutowicza Street 11/12Gdańsk 80-233Poland Department of Mechanical Engineering Iskenderun Technical UniversityIskenderunHatay 31200Turkiye

Magnesium and aluminum alloys continually attract interest as lightweight structural materials for transport applications. However, joining these dissimilar alloys is very challenging. The main obstacle that hinders progress in dissimilar Mg-Al joining is the formation of brittle intermetallic compounds(IMCs). As a solid-state joining technique, FSW is an excellent candidate to attenuate the deleterious IMC effects in dissimilar Al-Mg joining due to the inherent low heat inputs involved in the process. However, the IMCs, namely Al_(3)Mg_(2) and Al_(12)Mg_(17) phases, have also been reported to form during Al-Mg dissimilar FSW;their amount and thickness depend on the heat input involved;thus,the weld parameters used. Since the heat dissipated in the material during the welding process significantly affects the amount of IMCs,the heat input during FSW should be kept as low as possible to control and reduce the amount of IMCs. This review aims to critically discuss and evaluate the studies conducted in the dissimilar Al/Mg FSW through a scientometric analysis and also with a focus on the strategies recently applied to enhance joint quality. The scientometric analysis showed that the main research directions in Mg/Al FSW are the technological weldability of aluminum and magnesium during FSW, structural morphology, and mechanical properties of dissimilar welded joints. Considering the scope of application of the aforementioned joints, the low share of articles dealing with environmental degradation and operational cracking is surprising. This might be attributed to the need for well-developed strategies for obtaining high-quality and sustainable joints for applications. Thus, the second part of this review is conventional, focusing mainly on the new strategies for obtaining high-quality Mg/Al joints. It can be concluded that in addition to the necessity to optimum welding parameters to suppress the excessive heat to limit the amount and thickness of IMC formed and improv

关键词： Friction stir welding(FSW) Al-alloys Mg-alloys Dissimilar material welding Intermetallics Weld performance

Investigation of the sodium storage mechanism of iron fluoride hydrate cathodes using X-ray absorption spectroscopy and mossbauer spectroscopy

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2023年第2期77卷 535-542,I0014页

作者： Ghulam Ali Muhammad Akbar Faiza Jan Iftikhar Qamar Wali Beata Kalska Szostko dariusz Satuła Kyung Yoon Chung Energy Storage Research Center Korea Institute of Science and TechnologyHwarang-ro 14 gil 5Seongbuk-guSeoul 02792South Korea USPCAS-E National University of Sciences and Technology(NUST)H-12Islamabad 44000Pakistan Division of Energy&Environment Technology KIST SchoolKorea University of Science and Technology(UST)Hwarang-ro 14-gil-5Seongbuk-guSeoul 02792South Korea NUTECH School of Applied Sciences and Humanities National University of TechnologyIslamabad 44000Pakistan University of Białystok Faculty of ChemistryCiołkowskiego 1K15-424 BiałystokPoland University of Białystok Faculty of PhysicsCiołkowskiego 1L15-424 BiałystokPoland

Elucidation of a reaction mechanism is the most critical aspect for designing electrodes for highperformance secondary ***,we investigate the sodium insertion/extraction into an iron fluoride hydrate(FeF_(3)·0.5H_(2)O)electrode for sodium-ion batteries(SIBs).The electrode material is prepared by employing an ionic liquid 1-butyl-3-methylimidazolium-tetrafluoroborate,which serves as a reaction medium and precursor for F^(-)*** crystal structure of FeF_(3)·0.5H_(2)O is observed as pyrochlore type with large open 3-D tunnels and a unit cell volume of 1129A^(3).The morphology of FeF_(3)·0.5H_(2)O is spherical shape with a mesoporous *** microstructure analysis reveals primary particle size of around 10 *** FeF_(3)·0.5H_(2)O cathode exhibits stable discharge capacities of 158,210,and 284 mA h g^(-1) in three different potential ranges of 1.5-4.5,1.2-4.5,and 1.0-4.5 V,respectively at 0.05 C *** specific capacities remained stable in over 50 cycles in all three potential ranges,while the rate capability was best in the potential range of 1.5-4.5 *** electrochemical sodium storage mechanism is studied using X-ray absorption spectroscopy,indicating higher conversion at a more discharged ***-situ M?ssbauer spectroscopy strengthens the results for reversible reduction/oxidation of *** results will be favorable to establish high-performance cathode materials with selective voltage window for SIBs.

关键词： Iron fluoride Sodium-ion batteries Pyrochlore X-ray absorption spectroscopy Mössbauer spectroscopy

Diagnostic accuracy of serum biochemical fibrosis markers in children with chronic hepatitis B evaluated by receiver operating characteristics analysis

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2005年第45期11卷 7192-7196页

作者： dariusz Marek Lebensztejn Elzbieta Skiba Jolanta Tobolczyk Maria Elzbieta Sobaniec-Lotowska Maciej Kaczmarski Ⅲrd Department of Pediatrics Department of Children Allergology Department of Clinical Pathomorphology

METHODS： We determined the serum level of apolipoprotein A-I （APO A-I）, haptoglobin （HPT） and a-2 macroglobulin （A2I） with an automatic nephelometer in 63 children （age range 4-17 years, mean 10 years） with biopsy-verified chronic HBeAg-positive hepatitis B. Fibrosis stage and inflammation grade were assessed in a blinded fashion according to Batts and Ludwig. We defined mild liver fibrosis as a score ≤2 and advanced fibrosis as a score equal to 3. ROC analysis was used to calculate the power of the assays to detect advanced liver fibrosis （AccuROC, Canada）. RESULTS： Serum concentrations of APO A-I, HPT and A2M were not significantly different in patients with chronic hepatitis B compared to controls. However, APO A-I level of 1.19 ng/L had a sensitivity of 85.7% and a specificity of 60.7% （AUC = 0.7117, P = 0.035） to predict advanced fibrosis. All other serum biochemical markers and their combination did not allow a useful prediction. None of these markers was a good predictor of histologic inflammation. CONCLUSION： Apolipoprotein A-I may be a suitable serum marker to predict advanced liver fibrosis in children with chronic hepatitis B.

关键词： Chronic hepatitis B Liver fibrosis Children Apolipoprotein A-I Haptoglobin a-2 macroglobulin

Effects of Rhodiola rosea supplementation on mental performance,physical capacity,and oxidative stress biomarkers in healthy men

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Sport and Health Science 2018年第4期7卷 473-480页

作者： Ewa Jòwko Jerzy Sadowski Barbara Dlugolecka dariusz Gierczuk Benedykt Opaszowski Igor Cieslinski Department of Physiology and Biochemistry Faculty of Physical Education and Sport in Biala PodlaskaJòzef Pitsudski University of Physical Education in WarsawBiala Podlaska 21-500Poland Faculty of Physical Education and Sport in Biala Podlaska Jòzef Pilsudski University of Physical Education in WarsawBiala Podlaska 21-500Poland Department of Endocrinology Institute of Sport in WarsawWarsaw 01-982Poland Corresponding author.E-mail address：ewa.jowko@awf-bp.edu.pl

Purpose： The objective of this study was to investigate the effects of chronic Rhodiola rosea （R. rosea） supplementation on mental and physical performance, as well as hormonal and oxidative stress biomarkers. Methods： Twenty-six healthy male students received either R. rosea extract （600 mg/day; RR） or placebo （PL） in a randomized double-blind trial. Prior to supplementation （Term I） and following 4 weeks of supplementation （Term II）, the students underwent psychomotor tests for simple and choice reaction time, included in the Vienna Test System. Also, the subjects performed VO2peak test. Blood samples were obtained before and after the test to measure the hormonal profile （cortisol, testosterone, and growth hormone）, as well as the biomarkers of oxidative stress （lipid hydroperoxides, total antioxidant capacity, and superoxide dismutase） and muscle damage （creatine kinase）. Results： R. rosea ingestion shortened reaction time and total response time. Moreover, a greater relative increase in the number of correct responses was observed in RR group as compared to the PL group. No changes in endurance exercise capacity and hormonal profile were observed after R. rosea ingestion. R. rosea ingestion raised plasma total antioxidant capacity. It did not, however, affect other measured parameters. Conclusion： Chronic R. rosea ingestion does not affect physical performance, but can improve the results of some psychomotor tests （simple and choice reaction time） in young, healthy, and physically active men. The improvements in mental performance, however, at least in our study, seem not to be related to changes in cortisol release or antioxidant activity of R. rosea extract. Thus, the specific mechanisms responsible for these effects still need to be elucidated.2018 Published by Elsevier B.V. on behalf of Shanghai University of Sport. This is an open access article under the CC BY-NC-ND license. （http：//***/licenses/by-nc-nd/4.0/）.

关键词： Cortisol Endurance capacity Incremental exercise Men Oxidative stress Simple and choice reaction time Testosterone

Preoperative high level of D-dimers predicts unresectability of pancreatic head cancer

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2014年第36期20卷 13167-13171页

作者： Adam Durczynski Anna Kumor Piotr Hogendorf dariusz Szymanski Piotr Grzelak Janusz strzelczyk Department of General and Transplant Surgery Medical University of Lodz 90-153 Lodz Poland Department of Allergology and Pulmonary Diseases Medical University of Lodz 90-153 Lodz Poland Department of Radiology and Diagnostic Imaging Medical University of Lodz 90-153 Lodz Poland

AIM: To assess the value of D-dimer level in determining resectability of pancreatic cancer.

关键词： Pancreatic cancer D-dimers Portal blood Peripheral blood Bile Urine Pancreatic cancer respectability

Laser-induced white-light emission from graphene ceramics–opening a band gap in graphene

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Light(Science & Applications) 2015年第1期4卷 545-552页

作者： Wieslaw Strek Bartlomiej Cichy Lukasz Radosinski Pawel Gluchowski Lukasz Marciniak Mikolaj Lukaszewicz dariusz Hreniak Polish Academy of Sciences Institute of Low Temperatures and Structural Research50-422 WroclawPoland Wroclaw University of Technology Group of Chemical and Biochemical Processes50-370 WroclawPoland

Recent theoretical and experimental studies have indicated the existence of a new stable phase of carbon with mixed sp^(2) and sp^(3) hybridized bonds—*** a two-layered structure with sp^(2)/sp^(3) bonds may be observed after the photostimulation of highly oriented pyrolytic graphene with femtosecond laser *** hidden multistability of graphene may be used to create a semiconducting phase immersed in the semimetallic continuum,resulting in bandgap *** demonstrate that bandgap opening and light emission from graphene is possible using continuous-wave laser beams with wavelengths from the visible(405 nm)to the near-infrared range(975 nm).We demonstrate that without the application of cooling,the effective temperature of the emitting sample remains lower than 900 K,which is far below the value predicted by the theory of black-body ***,light emission from a graphene sample may be observed at temperatures as low as 10 K.

关键词： ceramics graphene photoluminescence white light

Impact of ultrasound and optical biometry on refractive outcomes of cataract surgery after penetrating keratoplasty in keratoconus

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Ophthalmology(English edition) 2019年第6期12卷 949-953页

作者： Katarzyna Krysik Anita Lyssek-Boron Dominika Janiszewska-Bil Edward Wylegala dariusz Dobrowolski Department of Ophthalmology with Pediatric Unit St.Barbara HospitalTrauma CentreSosnowiec 41-200Poland Department of Ophthalmology District Railway HospitalKatowice 40-760Poland Chair and Clinical Department of Ophthalmology School of Medicine with the Division of Dentistry in ZabrzeMedical University of Silesia in KatowiceKatowice 40-760Poland Hebei Provincial Eye Hospital Xingtai 054001Hebei ProvinceChina

AIM: To analyse the impact of ultrasound and optical intraocular lens(IOL) calculation methods on refractive outcomes of cataract phacoemulsification performed after penetrating keratoplasty(PK) in keratoconus. METHODS: Phacoemulsification cataract surgery was performed on 42 eyes of 34 patients with keratoconus who had previously undergone PK. The IOL power was determined by using both standard and corneal topography-derived keratometry using the SRK/T formula. We used two independent methods-ultrasound biometry(UB) and interferometry [optical biometry(OB)] for IOL calculation. The analysed data from medical records included demographics, medical history, best corrected visual acuity(BCVA) on Snellen charts, technique of IOL calculation and calculation formula and its impact on final refractive ***: BCVA ranged from 0.01 to 0.4(mean 0.09±0.19) before surgery and ranged from 0.2 to 0.7(mean 0.38±0.14) at 1 mo and from 0.2 to 1.0(mean 0.56±0.16)(P<0.05) at 3 mo, postoperatively. The refractive aim differed significantly from the refractive outcome in both the UB and OB groups(P<0.05). There was no statistically significant difference in the accuracy of the two biometry ***: The refractive aim in keratoconus eyes post-PK is not achieved with either ultrasound or OB.

关键词： ultrasound biometry optical biometry cataract surgery penetrating keratoplasty keratoconus

Studies on thermal decomposition of phenol binder using TG/DTG/DTA and FTIR-DRIFTS techniques in temperature range 20-500 °C

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

China Foundry 2018年第2期15卷 145-151页

作者： Artur Bobrowski dariusz Drozynski Beata Grabowska Karolina Kaczmarska Zaneta Kurleto–Koziol Marcin Brzezinski AGH University of Science and Technology Faculty of Foundry EngineeringKrakowpoland

This paper presents results of thermoanalytical and structural research on phenolic binder used in foundry for the preparation of moulding sand. The binder has been prepared based on resole type phenolic resin with the addition of ester hardener. The aim of the study was to determine the structural changes taking place in the phenolic binder under the influence of temperature. Results show that in the investigated range of temperatures, phenolic binder exhibits three exothermic thermal effects accompanying the decomposition process. The test results using the Diffuse Reflectance Infrared Fourier Transform Spectroscopy(DRIFTS) technique show that the addition of a hardener stabilizes the binder structure within methylene bridges. The reduction in the reaction rate observed in the DTA curve at about 330 °C can be associated with the formation of gaseous products by decomposition of the binder or, as suggested by the literature data, the formation of triple bonds and CN-HCN groups.

关键词： phenolic resin thermal decomposition IR spectroscopy thermal analysis DRIFTS

Pediatric non-alcoholic steatohepatitis:The first report on the ultrastructure of hepatocyte mitochondria

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2014年第15期20卷 4335-4340页

作者： Joanna M Lotowska Maria E Sobaniec-Lotowska Sylwia B Bockowska dariusz M Lebensztejn Department of General Pathomorphology Medical University of Bialystok15269 BialystokPoland Department of Medical Pathomorphology Medical University of Bialystok15269 BialystokPoland Department of Laboratory Diagnostics Maria Sklodowska-Curie Memorial Bialystok Oncology Center15027 BialystokPoland Department of Pediatrics Gastroenterology and AllergologyMedical University of Bialystok15274 BialystokPoland

AIM: To investigate the ultrastructure of abnormal hepatocyte mitochondria, including their cellular and hepatic zonal distribution, in bioptates in pediatric non-alcoholic steatohepatitis (NASH).

关键词： Pediatric non-alcoholic steatohepatitis Hepatocyte ultrastructure Megamitochondria with crystalline inclusions Foamy cytoplasm of hepatocytes