期刊文献+
共找到241篇文章
< 1 2 13 >
每页显示 20 50 100
Context-dependency in medicine:how neuronal excitability influences the impact of dopamine on cognition
1
作者 Mahboubeh Ahmadi Nahid Rouhi +1 位作者 Javad Mirnajafi-Zadeh Bechara J.Saab 《Neural Regeneration Research》 SCIE CAS 2025年第11期3225-3226,共2页
Dopamine,often termed the"feel-good"neurotransmitter,plays a crucial role in myriad physiological and psychological brain processes.While dopamine is primarily associated with pleasure,reward,and motivation,... Dopamine,often termed the"feel-good"neurotransmitter,plays a crucial role in myriad physiological and psychological brain processes.While dopamine is primarily associated with pleasure,reward,and motivation,its effects can be quite complex;and this complexity is further compounded when examining how dopamine functions in typical versus disease-affected neural circuits.In pa rticula r,epilepsy,characte rized by heightened brain excitability,is linked to cognitive dysfunction,and dopamine is implicated in elements of both its pathology and treatment.Neuroscience has been successful in describing the synaptic abnormalities believed to contribute to memory issues in epilepsy,aiding in the search for effective therapies for what persists as a major medical issue. 展开更多
关键词 DOPAMINE EPILEPSY primarily
下载PDF
Clinical and molecular features of human cystic echinococcosis in Tehran,Iran,2011-2019
2
作者 Narges Amani Hamedani Majid Pirestani Abdolhossein Dalimi 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2022年第12期558-567,共10页
Objective:To evaluate the clinical and molecular features of human cystic echinococcosis in Tehran,Iran.Methods:In this cross-sectional study,all human cystic echinococcosis patients admitted to Tehran’s hospitals fr... Objective:To evaluate the clinical and molecular features of human cystic echinococcosis in Tehran,Iran.Methods:In this cross-sectional study,all human cystic echinococcosis patients admitted to Tehran’s hospitals from 2011 to 2019 were enrolled,and demographic characteristics,clinical findings,and laboratory data were collected.Formalinfixed,paraffin-embedded and fresh tissue samples of 175 cystic echinococcosis patients were evaluated for molecular characterization.The samples’isolated DNA was used to amplify cytochrome c oxidaseⅠand NADH dehydrogenase subunitⅠgenes.Also,the morphological features of fresh samples were examined.Results:In total,175 patients with a mean age of 45(9-98)years were admitted to Tehran’s hospitals diagnosed with cystic echinococcosis.Moreover,the highest(26.9%)and the lowest(2.9%)prevalence of cystic echinococcosis cases were in the 16-30 and 1-15 years range,respectively.Male/female ratio was 0.96(49.1%vs.50.9%).The liver was affected in 92 patients(52.6%),and two or more organs were infected in 7 patients(4.0%).The cysts’diameter varied from 1 to 25 cm,and 96.0%of the patients had a single hydatid cyst.All patients underwent radical surgery and the PAIR technique was applied for all cases.No significant difference was observed between the protoscolex hooks of pulmonary and hepatic cysts.G1-G3 had the highest percentage(99.4%)over other identified G6 genotypes(0.6%).Conclusions:The sheep-dog cycle plays an important role in transmitting the human cystic echinococcosis infection in Tehran. 展开更多
关键词 Human cystic echinococcosis Clinical features GENOTYPE TEHRAN
下载PDF
Enhancing rock fragmentation prediction in mining operations:A hybrid GWO-RF model with SHAP interpretability 被引量:1
3
作者 ZHANG Yu-lin QIU Yin-gui +2 位作者 ARMAGHANI Danial Jahed MONJEZI Masoud ZHOU Jian 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第8期2916-2929,共14页
In the mining industry,precise forecasting of rock fragmentation is critical for optimising blasting processes.In this study,we address the challenge of enhancing rock fragmentation assessment by developing a novel hy... In the mining industry,precise forecasting of rock fragmentation is critical for optimising blasting processes.In this study,we address the challenge of enhancing rock fragmentation assessment by developing a novel hybrid predictive model named GWO-RF.This model combines the grey wolf optimization(GWO)algorithm with the random forest(RF)technique to predict the D_(80)value,a critical parameter in evaluating rock fragmentation quality.The study is conducted using a dataset from Sarcheshmeh Copper Mine,employing six different swarm sizes for the GWO-RF hybrid model construction.The GWO-RF model’s hyperparameters are systematically optimized within established bounds,and its performance is rigorously evaluated using multiple evaluation metrics.The results show that the GWO-RF hybrid model has higher predictive skills,exceeding traditional models in terms of accuracy.Furthermore,the interpretability of the GWO-RF model is enhanced through the utilization of SHapley Additive exPlanations(SHAP)values.The insights gained from this research contribute to optimizing blasting operations and rock fragmentation outcomes in the mining industry. 展开更多
关键词 BLASTING rock fragmentation random forest grey wolf optimization hybrid tree-based technique
下载PDF
The anti-neoplastic effects of metformin modulate the acquired phenotype of fbroblast cells in the breast cancer-normal fbroblast co-culture system
4
作者 SAMANEH MOSTAFAVI ZUHAIR MOHAMMAD HASSAN 《Oncology Research》 SCIE 2024年第3期477-487,共11页
Intracellular communications between breast cancer and fibroblast cells were reported to be involved in cancer proliferation,growth,and therapy resitance.The hallmarks of cancer fibroblast interactions,consisting of c... Intracellular communications between breast cancer and fibroblast cells were reported to be involved in cancer proliferation,growth,and therapy resitance.The hallmarks of cancer fibroblast interactions,consisting of caveolin 1(Cav1)and mono-carboxylate ransporter 4(MCT4)(metabolic coupling markers),along with IL-6,TGFB,and lactate secretion,are considered robust biomarkers predicting recurrence and metastasis.In order to promote a novel phenotype in normal fibroblasts,we predicted that breast cancer cells could be able to cause loss of Cavl and increase of MCT4,as well as elevate IL 6 and TGF in nearby nomal fibroblasts.We created a co culture model using breast cancer(4T1)and normal fibroblast(NIH3T3)cell lines cultured under specific experimental conditions in order to directly test our theory.Moreover,we show that long-term co-culture of breast cancer cells and normal fibroblasts promotes loss of Cavl and gain of MCT4 in adjacent fibroblasts and increase lactate secretion.These results were validated using the monoculture of each group separately as a control.In this system,we show that me tformin inhibits IL-6 and TGFB secretion and re expresses Cavl in both cells.However,MCT4 and lactate stayed high after treatment with metformin.In conclusion,our work shows that co-culture with breast cancer cells may cause signifcant alterations in the phenotype and secretion of normal fibroblasts.Metformin,however,may change this state and affect fibroblasts'acquired phenotypes.Moreover,mitochondrial inhibition by metformin after 8 days of treatment,signi ficantly hinders tumor growth in mouse model of breast cancer. 展开更多
关键词 Caveolin 1 Lactic acid METFORMIN NIH 3T3 cells Neoplasms
下载PDF
Platform Evolution in an Oligo-Miocene Back-arc Basin:An Example from the Central Iran Basin
5
作者 Masoud SHARIFI-YAZDI Amirhossein ENAYATI +2 位作者 Jamal SALEHI AGHDAM Mohammad BAHREHVAR Seyed Mustafa REZAEI 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第1期185-206,共22页
The Qom Formation is the most important hydrocarbon reservoir target in Central Iran.The Qom platform developed in a back-arc basin during the Oligo-Miocene due to the closing of the Tethyan Seaway.This formation cons... The Qom Formation is the most important hydrocarbon reservoir target in Central Iran.The Qom platform developed in a back-arc basin during the Oligo-Miocene due to the closing of the Tethyan Seaway.This formation consists of a variety of carbonate and non-carbonate facies deposited on a platform ranging from supratidal to basin.A combination of tectonic and eustatic events led to some lateral and vertical facies variations in the study area.Six third-order depositional sequences and related surfaces were identified regarding vertical facies changes in the studied sections of this Oligo-Miocene succession.According to all results and data,this succession was initially deposited during the Chattian upon a distally steepened ramp of siliciclastic-carbonate composition,including the Bouma sequence.Then,from the late Chattian to the Aquitanian,the platform changed into a homoclinal carbonate ramp with a gentle profile.With respect to tectonic activity,this phase was a calm period during the deposition of the Qom Formation.Finally,a drowned carbonate platform and a rimmed shelf emerged during the Burdigalian,terminated by the continental deposits of the Upper Red Formation.Regarding all geological characteristics,three main tectono-eustatic evolutionary phases have been recognized in the Qom back-arcbasin. 展开更多
关键词 carbonate ramp depositional facies submarine fan EUSTASY basement faults back-arc basin
下载PDF
Developing a novel big dataset and a deep neural network to predict the bearing capacity of a ring footing
6
作者 Ramin Vali Esmaeil Alinezhad +3 位作者 Mohammad Fallahi Majid Beygi Mohammad Saberian Jie Li 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第11期4798-4813,共16页
The accurate prediction of the bearing capacity of ring footings,which is crucial for civil engineering projects,has historically posed significant challenges.Previous research in this area has been constrained by con... The accurate prediction of the bearing capacity of ring footings,which is crucial for civil engineering projects,has historically posed significant challenges.Previous research in this area has been constrained by considering only a limited number of parameters or utilizing relatively small datasets.To overcome these limitations,a comprehensive finite element limit analysis(FELA)was conducted to predict the bearing capacity of ring footings.The study considered a range of effective parameters,including clay undrained shear strength,heterogeneity factor of clay,soil friction angle of the sand layer,radius ratio of the ring footing,sand layer thickness,and the interface between the ring footing and the soil.An extensive dataset comprising 80,000 samples was assembled,exceeding the limitations of previous research.The availability of this dataset enabled more robust and statistically significant analyses and predictions of ring footing bearing capacity.In light of the time-intensive nature of gathering a substantial dataset,a customized deep neural network(DNN)was developed specifically to predict the bearing capacity of the dataset rapidly.Both computational and comparative results indicate that the proposed DNN(i.e.DNN-4)can accurately predict the bearing capacity of a soil with an R2 value greater than 0.99 and a mean squared error(MSE)below 0.009 in a fraction of 1 s,reflecting the effectiveness and efficiency of the proposed method. 展开更多
关键词 Bearing capacity Ring footing Finite element limit analysis(FELA) BC-RF dataset Deep neural network(DNN)
下载PDF
Color and Gloss Changes of a Lignin-Based Polyurethane Coating under Accelerated Weathering
7
作者 Fatemeh Hassani Khorshidi Saeed Kazemi Najafi +3 位作者 Farhood Najafi Antonio Pizzi Dick Sandberg Rabi Behrooz 《Journal of Renewable Materials》 EI CAS 2024年第2期305-323,共19页
The purpose of this research study was to investigate the properties of polyurethane coatings based on lignin nano-particles.For this purpose,the prepared coatings were applied to pine wood surfaces and weathered arti... The purpose of this research study was to investigate the properties of polyurethane coatings based on lignin nano-particles.For this purpose,the prepared coatings were applied to pine wood surfaces and weathered artificially.Subsequently,color and gloss of the coatings were measured before and after the weathering test.Field emission scanning electron microscopy(FE-SEM)micrographs prepared from the coatings showed that the average size of nano-particles in the polyurethane substrate was approximately 500 nm.Nuclear magnetic resonance(13C-NMR)spectroscopy showed that strong urethane bonds were formed in the nano-lignin-based polyurethane.Differential calorimetric analysis(DSC)test revealed that the glass-transition temperature(Tg)of lignin nanoparticles modified with diethylenetriamine(DETA)was 112.8℃ and Tg of lignin nano-particles modified with ethylenediamine(EDA)was 102.5℃,which is lower than the Tg of un-modified lignin(114.6℃)and lignin modified with DETA(126.8℃)and lignin modified with EDA(131.3℃).The coatings modified with lignin nano-particles had a greater change in gloss.The lignin nano-particles in the modified coating are trapping hydroxyl radicals which reduces photoactivity and yellowing of the polyurethane by about 3 times compared to unmodified polyurethane coatings.After weathering test,the nano-lignin-based coating had a rougher surface with a lower contact angle(0.78°)compared to the unmodified polyurethane coating(0.85°). 展开更多
关键词 AMINATION propylene carbonate LIGNIN BIOPOLYMER polyurethane coating POLYOL UN SDG 13
下载PDF
An intrinsically self-healing and anti-freezing molecular chains induced polyacrylamide-based hydrogel electrolytes for zinc manganese dioxide batteries
8
作者 Haiyang Liao Wenzhao Zhong +8 位作者 Chen Li Jieling Han Xiao Sun Xinhui Xia Ting Li Abolhassan Noori Mir F.Mousavi Xin Liu Yongqi Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第2期565-578,I0013,共15页
The anti-freezing strategy of hydrogels and their self-healing structure are often contradictory,it is vital to break through the molecular structure to design and construct hydrogels with intrinsic anti-freezing/self... The anti-freezing strategy of hydrogels and their self-healing structure are often contradictory,it is vital to break through the molecular structure to design and construct hydrogels with intrinsic anti-freezing/self-healing for meeting the rapid development of flexible and wearable devices in diverse service conditions.Herein,we design a new hydrogel electrolyte(AF/SH-Hydrogel)with intrinsic anti-freezing/self-healing capabilities by introducing ethylene glycol molecules,dynamic chemical bonding(disulfide bond),and supramolecular interaction(multi-hydrogen bond)into the polyacrylamide molecular chain.Thanks to the exceptional freeze resistance(84%capacity retention at-20℃)and intrinsic self-healing capabilities(95%capacity retention after 5 cutting/self-healing cycles),the obtained AF/SH-Hydrogel makes the zinc||manganese dioxide cell an economically feasible battery for the state-of-the-art applications.The Zn||AF/SH-Hydrogel||MnO_(2)device offers a near-theoretical specific capacity of 285 m A h g^(-1)at 0.1 A g^(-1)(Coulombic efficiency≈100%),as well as good self-healing capability and mechanical flexibility in an ice bath.This work provides insight that can be utilized to develop multifunctional hydrogel electrolytes for application in next generation of self-healable and freeze-resistance smart aqueous energy storage devices. 展开更多
关键词 Flexible aqueous battery Hydrogel electrolyte ANTI-FREEZING SELF-HEALING Dual-dynamic reversible bond
下载PDF
Experimental and Finite Element Analysis of Corroded High-Pressure Pipeline Repaired by Laminated Composite
9
作者 Seyed Mohammad Reza Abtahi Saeid Ansari Sadrabadi +4 位作者 Gholam Hosein Rahimi Gaurav Singh Hamid Abyar Daniele Amato Luigi Federico 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第8期1783-1806,共24页
Repairs of corroded high-pressure pipelines are essential for fluids transportation under high pressure.One of the methods used in their repairs is the use of layered composites.The composite used must have the necess... Repairs of corroded high-pressure pipelines are essential for fluids transportation under high pressure.One of the methods used in their repairs is the use of layered composites.The composite used must have the necessary strength.Therefore,the experiments and analytical solutions presented in this paper are performed according to the relevant standards and codes,including ASME PCC-2,ASME B31.8S,ASME B31.4,ISO 24817 and ASME B31.G.In addition,the experimental tests are replicated numerically using the finite element method.Setting the strain gauges at different distances from the defect location,can reduce the nonlinear effects,deformation,and fluctuations due to the high pressure.The direct relationship between the depth of an axial defect and the stress concentration is observed at the inner side edges of the defect.Composite reparation reduces the non-linearities related to the sharp variation of the geometry and a more reliable numerical simulation could be performed. 展开更多
关键词 High-pressure pipeline composite repair ASME PCC-2 ISO 24817
下载PDF
Strategies used by helicobacter pylori to establish persistent infection 被引量:14
10
作者 Amin Talebi Bezmin Abadi 《World Journal of Gastroenterology》 SCIE CAS 2017年第16期2870-2882,共13页
Helicobacter pylori(H. pylori) is a Gram-negative and motile bacterium that colonizes the hostile microniche of the human stomach, then persists for the host's entire life, if not effectively treated. Clinically, ... Helicobacter pylori(H. pylori) is a Gram-negative and motile bacterium that colonizes the hostile microniche of the human stomach, then persists for the host's entire life, if not effectively treated. Clinically, H. pylori plays a causative role in the development of a wide spectrum of diseases including chronic active gastritis, peptic ulceration, gastric adenocarcinoma, and gastric mucosaassociated lymphoid tissue lymphoma. Due to the global distribution of H. pylori, it is no exaggeration to conclude that smart strategies are contributing to adaptation of the bacterium to its permanent host. Thirty-four years after the discovery of this bacterium, there are still many unanswered questions. For example, which strategies help the bacterium to survive in this inhospitable microniche? This question is slightly easier to answer if we presume the same clinical concept for both persistent infection and disease. Understanding the mechanisms governing H. pylori persistence will improve identification of the increased risk of diseases such as gastric cancer in patients infected with this bacterium. A well-defined and longterm equilibrium between the human host and H. pylori allows bacterial persistence in the gastric microniche; although this coexistence leads to a high risk of severe diseases such as gastric cancer. To escape the bactericidal activity of stomach acid, H. pylori secretes large amounts of surface-associated and cytosolic urease. The potential to avoid acidic conditions and immune evasion are discussed in order to explain the persistence of H. pylori colonization in the gastric mucosa, and data on bacterial genetic diversity are included. Information on the mechanisms related to H. pylori persistence can also provide the direction for future research concerning effective therapy and management of gastroduodenal disorders. The topics presented in the current review are important for elucidating the strategies used by H. pylori to help the bacterium persist in relation to the immune system and the many unfavorable features of living in the gastric microniche. 展开更多
关键词 HELICOBACTER PYLORI GASTRIC microniche PERSISTENT INFECTION GASTRIC cancer
下载PDF
Effects of acetic acid on microstructure and electrochemical properties of nano cerium oxide films coated on AA7020-T6 aluminum alloy 被引量:7
11
作者 H. Hasannejad T. Shahrabi M. Aliofkhazraei 《Rare Metals》 SCIE EI CAS CSCD 2009年第1期98-101,共4页
Nano cerium oxide films were applied on AA7020-T6 aluminum alloy and the effects of acetic acid concentration on the microstructure and electrochemical properties of the coated samples were investigated by using scann... Nano cerium oxide films were applied on AA7020-T6 aluminum alloy and the effects of acetic acid concentration on the microstructure and electrochemical properties of the coated samples were investigated by using scanning electron microscopy (SEM), X-ray diffraction (XRD), and potentiodynamic polarization methods. It has been found that by increasing the acetic acid/CeCl3·7H2O molar ratio, high uniform and crack-free films with well-developed grains were obtained and grain sizes of the films decreased. Elimination of cracks and decreasing grain size of the nano cerium oxide films caused corrosion resistance to increase. 展开更多
关键词 nano cerium oxide films acetic acid aluminum alloy electrochemical property MICROSTRUCTURE
下载PDF
Wettability alteration and oil recovery by spontaneous imbibition of smart water and surfactants into carbonates 被引量:9
12
作者 Saeb Ahmadi Mostafa Hosseini +2 位作者 Ebrahim Tangestani Seyyed Ebrahim Mousavi Mohammad Niazi 《Petroleum Science》 SCIE CAS CSCD 2020年第3期712-721,共10页
Naturally fractured carbonate reservoirs have very low oil recovery efficiency owing to their wettability and tightness of matrix.However,smart water can enhance oil recovery by changing the wettability of the carbona... Naturally fractured carbonate reservoirs have very low oil recovery efficiency owing to their wettability and tightness of matrix.However,smart water can enhance oil recovery by changing the wettability of the carbonate rock surface from oilwet to water-wet,and the addition of surfactants can also change surface wettability.In the present study,the effects of a solution of modified seawater with some surfactants,namely C12 TAB,SDS,and TritonX-100(TX-100),on the wettability of carbonate rock were investigated through contact angle measurements.Oil recovery was studied using spontaneous imbibition tests at 25,70,and 90°C,followed by thermal gravity analysis to measure the amount of adsorbed material on the carbonate surface.The results indicated that Ca2+,Mg2+,and SO42-.ions may alter the carbonate rock wettability from oil-wet to water-wet,with further water wettability obtained at higher concentrations of the ions in modified seawater.Removal of NaCl from the imbibing fluid resulted in a reduced contact angle and significantly enhanced oil recovery.Low oil recoveries were obtained with modified seawater at 25 and 70°C,but once the temperature was increased to 90°C,the oil recovery in the spontaneous imbibition experiment increased dramatically.Application of smart water with C12 TAB surfactant at 0.1 wt%changed the contact angle from 161°to 52°and enhanced oil recovery to 72%,while the presence of the anionic surfactant SDS at 0.1 wt%in the smart water increased oil recovery to 64.5%.The TGA analysis results indicated that the adsorbed materials on the carbonate surface were minimal for the solution containing seawater with C12 TAB at 0.1 wt%(SW+CTAB(0.1 wt%)).Based on the experimental results,a mechanism was proposed for wettability alteration of carbonate rocks using smart water with SDS and C12 TAB surfactants. 展开更多
关键词 Smart water SURFACTANTS Carbonate rock Wettability alteration
下载PDF
低渗透含水层储气库储气过程中气-水-岩相互作用及储气量影响因素 被引量:7
13
作者 TOOSEH Esmaeel Kazemi JAFARI Arezou TEYMOURI Ali 《石油勘探与开发》 SCIE EI CAS CSCD 北大核心 2018年第6期1053-1058,共6页
利用室内岩心实验研究了低渗透含水层储气库天然气储气过程中气-水-岩相互作用以及影响储气过程的主要参数。研究表明,实验条件下储气量占岩心孔隙体积的百分比为6%~20%。注气速度对储气量有重要影响,注气速度较高时,储气量较高。提高... 利用室内岩心实验研究了低渗透含水层储气库天然气储气过程中气-水-岩相互作用以及影响储气过程的主要参数。研究表明,实验条件下储气量占岩心孔隙体积的百分比为6%~20%。注气速度对储气量有重要影响,注气速度较高时,储气量较高。提高压力也会使储气量增加。统计分析表明,注气速度比压力对储气量的影响更大。储气时间对储气过程也有影响,长期储存后会有大部分天然气滞留在储集层中无法被采出。原子吸收光谱分析表明,将天然气注入盐水饱和岩心的过程中,盐水中的离子浓度和水蒸发量增大,可能形成沉淀物,降低岩石的孔隙度和渗透率。气相色谱分析表明,在岩心中储存后,天然气中二氧化碳浓度降低,甲烷浓度增加。 展开更多
关键词 地下储气库 天然气 储气量 含水层 注气速度 注气压力
下载PDF
A model to determine hole spacing in the rock fracture process by non-explosive expansion material 被引量:13
14
作者 Shobeir Arshadnejad Kamran Goshtasbi Jamshid Aghazadeh 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2011年第5期509-514,共6页
The application of the non-explosive expansion material (NEEM) is widely used as the controlled fracture method in quarry min- ing, especially in hard rocks. The pressure of NEEM is an important parameter in causing... The application of the non-explosive expansion material (NEEM) is widely used as the controlled fracture method in quarry min- ing, especially in hard rocks. The pressure of NEEM is an important parameter in causing rock fracture. An empirical model based on hole spacing was developed to determine the pressure of NEEM in the rock fracture process. Primarily, the empirical model was developed by the mathematical method, utilizing dimensional analysis. Then, the Phase2 code, which is based on the finite element method, was utilized to predict crack growth in rocks. The results of numerical analysis show slight deviations from the empirical model. Hence, the polynomial re- gression analysis was used to modify the model. Finally, the modified model shows a good agreement with the results gained from numerical modeling. 展开更多
关键词 rock fracture dimensional analysis finite element method non-explosive quarry mining
下载PDF
Role of Chloride Ion and Dissolved Oxygen in Electrochemical Corrosion of AA5083-H321 Aluminum-Magnesium Alloy in NaCl Solutions under Flow Conditions 被引量:9
15
作者 K.Jafarzadeh T.Shahrabi +1 位作者 S.M.M.Hadavi M.G.Hosseini 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2007年第5期623-628,共6页
Flow-induced corrosion consists electrochemical and mechanical components. The present paper has to assessed the role of chloride ion and dissolved oxygen in the electrochemical component of flow induced corrosion for... Flow-induced corrosion consists electrochemical and mechanical components. The present paper has to assessed the role of chloride ion and dissolved oxygen in the electrochemical component of flow induced corrosion for AA5083-H321 aluminum-magnesium alloy which is extensively used in the construction of high-speed boats, submarines, hovercrafts, and desalination systems, in NaCI solutions. Electrochemical tests were carried out at flow velocities of 0, :2, 5, 7 and 10 m/s, in aerated and deaerated NaCI solutions with different sodium chloride concentrations. The results showed that the high rate of oxygen reduction under hydrodynamic conditions causes an increase in the density of pits on the surface. The increase of chloride ions concentration under flow conditions accelerates the rate of anodic reactions, but have no influence on the cathodic reactions. Thus, in the current work, it was found that under flow conditions, due to the elimination of corrosion products inside the pits, corrosion resistance of the alloy is increased. 展开更多
关键词 CORROSION FLOW NaCl solution AA5083-H321 aluminum-magnesium alloy Chloride ion OXYGEN
下载PDF
Performance evaluation of a modified step-feed anaerobic/anoxic/oxic process for organic and nutrient removal 被引量:6
16
作者 A.R.Majdi Nasab S.M.Soleymani +1 位作者 M.Nosrati S.M.Mousavi 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第3期394-403,共10页
A pilot scale modified step-feed process was lmproved to increase nutrient/N ano P) ano organic removal operations from municipal wastewater. It combined the step-feed process and a method named "University of Cape ... A pilot scale modified step-feed process was lmproved to increase nutrient/N ano P) ano organic removal operations from municipal wastewater. It combined the step-feed process and a method named "University of Cape Town (UCT)". The effect of nutrient ratios and inflow distribution ratios were studied. The highest uptake efficiency of 95% for chemical oxygen demand (COD) has been achieved at the inflow distribution ratio of 40/35/25. However, maximum removal efficiency obtained for total nitrogen (TN) and phosphorus at 93% and 78%, respectively. The average mixed liquor suspended solids (MLSS) was 5500 mg·L- 1. In addition, convenient values for dissolved oxygen (DO) concentration, and pH were obtained throughout different stages. The proposed system was identified to be an appropriate enhanced biological nutrient removal process for wastewater treatment plants owing to relatively high nutrient removal, sturdy sludge settle ability and COD removal. 展开更多
关键词 Biological nutrient remova Step-feed bioreactor NITRIFICATION DENITRIFICATION Phosphorus removal
下载PDF
Parametric Study of Two-Body Floating-Point Wave Absorber 被引量:6
17
作者 Atena Amiri Roozbeh Panahi Soheil Radfar 《Journal of Marine Science and Application》 CSCD 2016年第1期41-49,共9页
In this paper, we present a comprehensive numerical simulation of a point wave absorber in deep water. Analyses are performed in both the frequency and time domains. The converter is a two-body floating-point absorber... In this paper, we present a comprehensive numerical simulation of a point wave absorber in deep water. Analyses are performed in both the frequency and time domains. The converter is a two-body floating-point absorber (FPA) with one degree of freedom in the heave direction. Its two parts are connected by a linear mass-spring-damper system. The commercial ANSYS-AQWA software used in this study performs well in considering validations. The velocity potential is obtained by assuming incompressible and irrotational flow. As such, we investigated the effects of wave characteristics on energy conversion and device efficiency, including wave height and wave period, as well as the device diameter, draft, geometry, and damping coefficient. To validate the model, we compared our numerical results with those from similar experiments. Our study results can clearly help to maximize the converter's efficiency when considering specific conditions. 展开更多
关键词 floating-point absorber wave energy energy absorption Wave Energy Converter (WEC) Power Take Off (PTO) numerical simulation
下载PDF
Bacteriophages and their applications in the diagnosis and treatment of hepatitis B virus infection 被引量:5
18
作者 Babak Bakhshinejad Majid Sadeghizadeh 《World Journal of Gastroenterology》 SCIE CAS 2014年第33期11671-11683,共13页
Hepatitis B virus(HBV) infection is a major global health challenge leading to serious disorders such as cirrhosis and hepatocellular carcinoma. Currently, there exist various diagnostic and therapeutic approaches for... Hepatitis B virus(HBV) infection is a major global health challenge leading to serious disorders such as cirrhosis and hepatocellular carcinoma. Currently, there exist various diagnostic and therapeutic approaches for HBV infection. However, prevalence and hazardous effects of chronic viral infection heighten the need to develop novel methodologies for the detection and treatment of this infection. Bacteriophages, viruses that specifically infect bacterial cells, with a long-established tradition in molecular biology and biotechnology have recently been introduced as novel tools for the prevention, diagnosis and treatment of HBV infection. Bacteriophages, due to tremendous genetic flexibility, represent potential to undergo a huge variety of surface modifications. This property has been the rationale behind introduction of phage display concept. This powerful approach, together with combinatorial chemistry, has shaped the concept of phage display libraries with diverse applications for the detection and therapy of HBV infection. This review aims to offer an insightful overview of the potential of bacteriophages in the development of helpful prophylactic(vaccine design), diagnostic and therapeutic strategies for HBV infection thereby providing new perspec-tives to the growing field of bacteriophage researches directing towards HBV infection. 展开更多
关键词 BACTERIOPHAGE Hepatitis B virus Phage dis-play Phage library BIOPANNING Diagnosis Treatment Vaccine development
下载PDF
Modeling of fine coal flotation separation based on particle characteristics and hydrodynamic conditions 被引量:12
19
作者 B. Shahbazi S. Chehreh Chelgani 《International Journal of Coal Science & Technology》 EI 2016年第4期429-439,共11页
Flotation is a complex multifaceted process that is widely used for the separation of finely ground minerals. The theory of froth flotation is complex and is not completely understood. This fact has been brought many ... Flotation is a complex multifaceted process that is widely used for the separation of finely ground minerals. The theory of froth flotation is complex and is not completely understood. This fact has been brought many monitoring challenges in a coal processing plant. To solve those challenges, it is important to understand the effect of different parameters on the fine particle separation, and control flotation performance for a particular system. This study is going to indicate the effect of various parameters (particle Characteristics and hydrodynamic conditions) on coal flotation responses (flotation rate constant and recovery) by different modeling techniques. A comprehensive coal flotation database was prepared for the statistical and soft computing methods. Statistical factors were used for variable selections. Results were in a good agreement with recent theoretical flotation investigations. Computational models accurately can estimate flotation rate constant and coal recovery (correlation coefficient 0.85, and 0.99, respectively). According to the results, it can be concluded that the soft computing models can overcome the complexity of process and be used as an expert system to control, and optimize parameters of coal flotation process. 展开更多
关键词 Coal processing FLOTATION MODELING Particle characteristics - Hydrodynamic conditions
下载PDF
Cu-Zn-Al2O3 nanocomposites: study of microstructure, corrosion, and wear properties 被引量:4
20
作者 Mohammad Baghani Mahmood Aliofkhazraei Mehdi Askari 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2017年第4期462-472,共11页
Alumina nanoparticles were added to a Cu-Zn alloy to investigate their effect on the microstructural,tribological,and corrosion properties of the prepared alloys. Alloying was performed using a mixture of copper and z... Alumina nanoparticles were added to a Cu-Zn alloy to investigate their effect on the microstructural,tribological,and corrosion properties of the prepared alloys. Alloying was performed using a mixture of copper and zinc powders with 0vol% and 5vol% of α-Al nanopowder in a satellite ball mill. The results showed that the Cu-Zn solid solution formed after 18 h of mechanical alloying. The mechanically alloyed powder was compacted followed by sintering of the obtained green compacts at 750°C for 30 min. Alumina nanoparticles were uniformly distributed in the matrix of the Cu-Zn alloy. The tribological properties were evaluated by pin-on-disk wear tests,which revealed that,upon the addition of alumina nanoparticles,the coefficient of friction and the wear rate were reduced to 20% and 40%,respectively. The corrosion properties of the samples exposed to a 3.5wt% Na Cl solution were studied using the immersion and potentiodynamic polarization methods,which revealed that the addition of alumina nanoparticles reduced the corrosion current of the nanocomposite by 90%. 展开更多
关键词 NANOCOMPOSITES copper zinc alloys ALUMINA MICROSTRUCTURE CORROSION wear properties
下载PDF
上一页 1 2 13 下一页 到第
使用帮助 返回顶部