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کاربرد نوع شرط:
- جایگاه : پژوهشی
- مجله: Gas Processing Journal
- نوع مقاله: Journal Article
- کلمات کلیدی: Solar Energy,Absorption chiller,LiBr-H2O refrigerant,absorption refrigeration system
- چکیده:
- چکیده انگلیسی: In recent years, the use of absorption chillers in air conditioning applications has increased in favor of less power consumption. Since absorption chillers require much less power compared to other common devices in the air conditioning industry, extensive efforts have been made in order to model, design, and optimize these systems. This study has investigated the effect of using solar energy on parallel and series two-stage refrigeration systems. First, both systems were designed, and then by connecting the solar collector to the absorption refrigeration system, the COP of the system and fuel consumption was calculated. Then, the impact of changing the evaporator’s temperature on the system’s COP was studied. The thermodynamic analysis of the system was conducted and the internal variables, such as pressure and temperature of different parts including the condenser and the evaporator, were calculated. Results indicate that the COP of the parallel cycle with a LiBr-H2O working fluid is higher than that of a series cycle, so this leads to a significant drop in fuel consumption.
- انتشار مقاله: 22-02-1398
- نویسندگان: Farshad Moradi Kashkooli,Mohsen Rezaeian,Mostafa Sefidgar,Madjid Soltani,Mostafa Mafi
- مشاهده
- جایگاه : پژوهشی
- مجله: Geopersia
- نوع مقاله: Journal Article
- کلمات کلیدی: analytic hierarchy process,GIS,Susceptibility,Landslide,Wi,FR
- چکیده: دامنههای مرتفع تهران به علت شرا یط اقلیم ی، ویژگ یهای زم ین
شناسی و مورفولوژیکی مستعد وقوع زمین لغزش می-باشند .بنابرا ین
تهیه نقشه آسیب پذیریزمین لغزش منطقه اهمیت حی اتی دارد. برا ی
رسیدن به این هدف نقشههای موضوعی شامل: زم ینلغزش های رخ
داده،لیتولوژی، شیب، جهت شیب، انحناء شیب، فاصله تا آبراهه، فاصله
تا گسل، ارتفاع، کاربری اراضی و بارش مورد استفاده قرار گرفته شده
است. سپس به کلاسهای نقشههای موضوعی رستری وزنی اختصاص
داده شد،که با همپوشانی آنها نقشه نهایی تهی ه شد و هر سلول آن
می (LSI) دارای شاخص مشخصی از مقدار آسیب پذیری زمین لغزش
باشد.در نهایت سه نقشه تهیه شده برای ارزیابی روش های بکار رفته
با هم مقایسه شدند. این نقشهها پس از طبقه بندی نشان دهنده نقشه
آسیب پذیری منطقه مورد مطالعه می باشند. در منطقه مورد مطالعه
74 درصد از زمین لغزشها در واحد های شیلی رخ داده اند.اطلاعات به
دست آمده نشان دادند که لایههای اطلاعاتی لیتولوژی، شیب، فاصله
تا آبراهه و فاصله تا گسل فاکتورهای مهمی در منطقه مورد مطالعه
میباشند. نتایج مقایسه های انجام شده نشان داد که مناطق فعال
زمین لغزش بطور کامل در کلاسهای با آسیب پذ یری زی اد و خیل ی
99 درصد از این زمین لغزشهای فعال در / زیاد قرار نمی گیرند، اما 6
مناطق با آسیب پذیری زیاد و خیلی زیاد در نقشه تهیه شده با روش
درصد AHP 5/ رخ دادهاند. در حالی که این مقادیر برای روش 74 WI
FR و WI درصد میباشد. بنابراین روشهای FR 2/ و برای روش 97
AHP تصویر واقعیتری از توزیع خطر زم ین لغزش نسبت به روش
نشان میدهند.
- چکیده انگلیسی: The high hillsides of the Tehran metropolis are prone to landslides due to the climatic conditions and the geological, geomorphological
characteristics of the region. Therefore, it is vitally important that a landslide susceptibility map of the region be prepared. For this
purpose, thematic layers including landslide inventory, lithology, slope, aspect, curvature, distance to stream, distance to fault,
elevation, land use, and precipitation were used. Next, weighted raster thematic maps with assigned values for their classes were
multiplied by the corresponding weights and combined to yield a simple map where each cell has a certain landslide susceptibility
index (LSI) value. After reclassification, this represents the final susceptibility map of the study area. Finally the three maps were
compared to assess the strength of the corresponding methods. In this study area, 74% of landslides occurred in highly or completely
shaly units. Lithology, slope, distance to fault and distance to stream data layers were found to be important factors in the study area.
The outcome of this comparison was the conclusion that the active landslide zones do not completely fit into the high and very high
susceptibility classes. However, 99.6% of these landslide zones fall into the high and very high susceptibility zones of the bivariate
statistics (WI) method, or 74.5% in the case of the analytic hierarchy process (AHP) method and 97.2% with the frequency ratio (FR)
method. The results showed the WI and FR methods to give a more realistic picture of the actual distribution of landslide susceptibility
than the AHP method.
- انتشار مقاله: 06-12-1391
- نویسندگان: Samad Moradi,Mohsen Rezaei
- مشاهده
- جایگاه : پژوهشی
- مجله: Geopersia
- نوع مقاله: Journal Article
- کلمات کلیدی: Fuzzy,Yazd,Groundwater,Drinking Water,Water Quality Index
- چکیده:
- چکیده انگلیسی: Fuzzy Water Quality Index (FWQI) was applied in order to assess the degree of drinking water resources in Yazd province, Iran. This
study has also offered the creation of a new fuzzy water quality index (FWQI) to evaluate this tool’s applicability. 12 chemical
parameters including toxic and non-toxic heavy metals measured in 71 groundwater samples collected from drinking water resources
in rural areas were used. In FWQI, input data are categorized into three linguistic terms (“Desirable” or “Low”, “Acceptable” or
“Medium” and “Not-acceptable” or “High”) based on water quality standards for drinking water, Whereas the output data are
categorized into five classes (“Poor”, “Fair”, “Medium”, “Good” and “Excellent”) based on water quality index (WQI). The results
show that 8 groundwater samples were classified in the “Excellent” class with a certainty level of 5.33-76.67%, 41 samples in the
“Good” group with a certainty level of 8.5-96.5%, 8 samples were in the “Medium” category with a certainty level of 14-93.5%, 1
sample in the “Fair” level with a certainty level of 36.5%, and 13 samples were classified in the “Poor” class with a certainty level of
54.8-81.5% for potable purposes. The proposed Index can be a useful tool to be used in decision-making and environmental.- انتشار مقاله: 13-07-1391
- نویسندگان: Amir Saberi Nasr,Mohsen Rezaei,Majid Dashti Barmaki
- مشاهده
- جایگاه : پژوهشی
- مجله: Research Journal of Pharmacognosy
- نوع مقاله: Journal Article
- کلمات کلیدی: Mitochondria,Apoptosis,Sirt3,ROS,Capparis spinosa
- چکیده:
- چکیده انگلیسی: Background and objectives: Beside its nutritional role, caper (Capparis spinosa) has long been used as an analgesic, anti-inflammatory, anti-diabetic and anti-cancer remedy. In the present study, we tested whether this plant can make effective changes in Sirt3 and mitochondrial function in colorectal carcinoma cell line since mitochondrial dysfunction has long been implicated in both cancer and diabetes and benefit confers by caper in these diseases might be due to mitochondrial alterations. Methods: Total flavonoids and phenolics were assayed using colorimetric tests. Cytotoxicity of a phenolic-flavonoid rich extract of caper collected from two different geographical regions (south and west) were mechanistically studied in HT-29 cell line. Activity of an essential mitochondrial enzyme, Sirt3 has also been evaluated along with other parameters. IC50 of extracts were determined by MTT cytotoxicity assay, cell death and mitochondrial membrane potential were evaluated via flow cytometric analysis. Also, at IC50 concentrations, Sirt3 activity was determined fluorimetrically. Results: The results showed that caper induced significant cytotoxicity in HT-29 cells followed by mitochondrial membrane potential collapse, ROS overproduction, Sirt3 activity alteration and cell death. Conclusions: The above-mentioned cytotoxic parameters were inversely proportional to the phenolic and flavonoid contents of the extract showing that other mechanisms beyond their antioxidant capacities may contribute to their anti-cancer effects. In other term, these results suggest that antioxidant capacity may not directly contribute to the anticancer property.
- انتشار مقاله: 05-06-1396
- نویسندگان: Forouzan Khodaei,Mohsen Rezaei*,Mahmoud Hashemitabar,Marzieh Jafari,Amir Siahpoosh,Mahmood Reza Moein
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Physical Activity and Hormones
- نوع مقاله: Journal Article
- کلمات کلیدی: Alkaline phosphatase,Aspartate Aminotransferase,Alanine aminotransferase,Exhaustive aerobic exercise
- چکیده:
- چکیده انگلیسی: Introduction: There are many indications that hepatic enzymes levels in the blood and exercise have some kind of association although it is not well known; therefore, the purpose of this study was to examine the effect of an exhaustion session exercise on hepatic enzymes levels in nonathletic males and females. Material & Methods: Sixteen healthy nonathletic males (aged 30±5.4 years, weight 74.8±13 kg; mean ± SD) and females (aged 25.8±2.2 years, weight 57±9 kg; mean ± SD) participated as subjects in this study. Blood samples were collected at before and 2 hours after an exhaustion exercise. Results: The results showed that the baseline level of alanine aminotransferase (ALT) was higher in males than females (t = 2.1; P = 0.04). On the other hand, the results showed that alkaline phosphatase (ALP) increased (t = 2.4; P = 0.02) in the male group compare to the female group; while for ALT and aspartate aminotransferase (AST) levels no significant different were observed between groups and no significant changes were observed after the exercise. Conclusion: Although, there was the significant differences in ALT level between males and females, but hepatic enzymes were not affected by an exhaustion session exercise.
- انتشار مقاله: 03-11-1399
- نویسندگان: Mohsen Rezaei,Fatemeh Khodaei
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Immunology
- نوع مقاله: Journal Article
- کلمات کلیدی: Saliva,Dental caries,Immunoglobulins
- چکیده:
- چکیده انگلیسی: Background: Early Childhood Caries (ECC) is one of the most common chronic child-hood diseases. In spite of the global decrease in dental caries in the past decades, ECC has become a significant problem in many developing countries and also in a few indus-trialized nations. Saliva as a host factor can play an important role in the process of den-tal caries.
Objective: The aim of this study was to compare sIgA and IgG as saliva components between ECC and caries-free groups.
Methods: In this cross-sectional study, samples of unstimulated saliva of 90 children (45 in ECC group & 45 in caries-free group) were taken with Scully method. Then the concentration levels of sIgA and IgG were measured with Enzyme Linked Immunosorbent Assay and Single Radial Im-munodiffusion methods.
Results: Mean concentration levels of salivary sIgA and IgG were significantly higher among children with ECC (p<0.05). There was also a weak inverse correlation between sIgA level and DMFT index in ECC group but it was not statistically significant (p=0.056).
Conclusion: The high concentration of salivary im-munoglobulin in children with ECC may be associated with an increased antigenic load, leading to high production of antibodies.- انتشار مقاله: 17-05-1395
- نویسندگان: Ali Bagherian,Abdullah Jafarzadeh,Mohsen Rezaeian,Shima Ahmadi,Mohammad Taghi Rezaity
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Basic Medical Sciences
- نوع مقاله: Journal Article
- کلمات کلیدی: Apoptosis,AFM,ROS,HT-29 cancer cell,Mesobuthus eupeus venom,Mitochondrial membrane potential
- چکیده:
- چکیده انگلیسی: Objective(s): The purpose of this study was to investigate cytotoxicity and membrane toxicity effects induced by Mesobuthus eupeus venom (MEV) on the HT-29 cell line.
Materials and Methods: To determine the in vitro cytotoxicity via MTT assays, HT-29 (as cancer cell line) and Hek-293T (as normal cell) were treated through different concentrations of MEV, and cytotoxicity effects were then measured through assessment of mitochondrial membrane potential (ΔΨm), reactive oxygen species (ROS) generation, and apoptosis induction. The colony formation assay was performed to measure the antiproliferative effect of MEV on HT-29 cells. Nuclei alterations were also observed during apoptosis following DAPI staining. Besides, atomic force microscopy (AFM) was used to detect alterations in morphology and ultrastructure of the cells at a nanoscale level.
Results: According to MTT and clonogenic assays, MEV caused a significant decrease in cell viability and proliferation of HT-29 cells while it did not have any impact on normal cells and the IC50 value was found to be 10 µg/ml. Induction of apoptosis was also confirmed by flowcytometric analysis in HT-29 cells. Moreover, the results indicated that MEV had led to a suppression of proliferation and induction of apoptosis through increased ROS and depolarization of mitochondria. Furthermore, AFM imaging demonstrated apoptosis cell death after being treated with MEV in HT-29 cells.
Conclusion: This study showed that MEV had an antiproliferative effect on HT-29 cells by inducing apoptosis through the mitochondria signaling pathway. These findings suggested that MEV could be used as a promising natural remedy for cancer treatment.- انتشار مقاله: 13-03-1398
- نویسندگان: Massood Valizade,Atefeh Raesi Vanani,Mohsen Rezaei,Layasadat Khorsandi,Leila Zeidooni,Masoud Mahdavinia
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Basic Medical Sciences
- نوع مقاله: Journal Article
- کلمات کلیدی: Apoptosis,AFM,ROS,HT-29 cancer cell,Mesobuthus eupeus venom,Mitochondrial membrane potential
- چکیده:
- چکیده انگلیسی: Objective(s): The purpose of this study was to investigate cytotoxicity and membrane toxicity effects induced by Mesobuthus eupeus venom (MEV) on the HT-29 cell line.
Materials and Methods: To determine the in vitro cytotoxicity via MTT assays, HT-29 (as cancer cell line) and Hek-293T (as normal cell) were treated through different concentrations of MEV, and cytotoxicity effects were then measured through assessment of mitochondrial membrane potential (ΔΨm), reactive oxygen species (ROS) generation, and apoptosis induction. The colony formation assay was performed to measure the antiproliferative effect of MEV on HT-29 cells. Nuclei alterations were also observed during apoptosis following DAPI staining. Besides, atomic force microscopy (AFM) was used to detect alterations in morphology and ultrastructure of the cells at a nanoscale level.
Results: According to MTT and clonogenic assays, MEV caused a significant decrease in cell viability and proliferation of HT-29 cells while it did not have any impact on normal cells and the IC50 value was found to be 10 µg/ml. Induction of apoptosis was also confirmed by flowcytometric analysis in HT-29 cells. Moreover, the results indicated that MEV had led to a suppression of proliferation and induction of apoptosis through increased ROS and depolarization of mitochondria. Furthermore, AFM imaging demonstrated apoptosis cell death after being treated with MEV in HT-29 cells.
Conclusion: This study showed that MEV had an antiproliferative effect on HT-29 cells by inducing apoptosis through the mitochondria signaling pathway. These findings suggested that MEV could be used as a promising natural remedy for cancer treatment.- انتشار مقاله: 13-03-1398
- نویسندگان: Massood Valizade,Atefeh Raesi Vanani,Mohsen Rezaei,Layasadat Khorsandi,Leila Zeidooni,Masoud Mahdavinia
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Basic Medical Sciences
- نوع مقاله: Journal Article
- کلمات کلیدی: oxidative stress,Diabetes Mellitus,Apotransferrin,Glycation
- چکیده:
- چکیده انگلیسی: Objective(s) Nonenzymatic glycosylation (glycation) occurs in many macromolecules in aging and diabetes due to exposure of biomolecules to high level of glucose. Glycation can changes function, activities and structure of many biomolecules. Considering this important role of transferrin (Trf) in iron transport and antioxidant activity in plasma this study was carried out to investigate the effect of glycation in these processes. Materials and Methods In this study, human apo-Trf (5 mg/ml in sodium phosphate buffer pH= 7.4) was treated with different concentrations of glucose in different period of times (10 days and 20 days). Rate of glycation was measured using thiobarbituric acid method. The effect of glycation on iron binding antioxidant capacity of apo-Trf was investigated using two methods (RBC hemolysis and fluorescent). Results Result showed that rate of glycation of apo-Trf was increased with increase in glucose concentration and time of incubation (P< 0.05). Lower iron binding antioxidant capacity was observed for glycted Trf as compared to native Trf (P< 0.05). Conclusion Impairment of antioxidant capacity of glycated Trf can suggest a relationship between glycation of Trf and oxidative stress that occurs due to hyperglycemia in diabetic patients.
- انتشار مقاله: 07-07-1394
- نویسندگان: Mohammad Taghi Goodarzi,Mojtaba Rashidi,Mohsen Rezaei
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Chemistry and Chemical Engineering
- نوع مقاله: Journal Article
- کلمات کلیدی: Fire,risk assessment,Explosion,Dow F&EI,Combined Cycle Power Plant
- چکیده:
- چکیده انگلیسی: Fire and explosion are the most prevalent accidents in chemical and process industries. Hence, identification of the hazard factors and the methods of controlling these two major accidents are very important in the process industries. In this paper, fire and explosion hazards of some process units at a combined cycle power plant have been estimated using the Dow fire and explosion index. The results of this study show that methane fueled turbine has the highest value of Dow index which is 321, turbine unit with gas oil and gas oil storage site have the Dow index values of 147.5 and 35.5 respectively. The loss control credit factor for methane fueled turbine unit was 0.36 and the Actual Maximum Probable Property Damage was 4.12 US million dollars. Maximum Probable Days Outage is estimated to be 50 days and finally, the loss due to unit pauses is calculated to be 3.03 US million dollars. In addition, the findings of the current study show that the gas oil storage unit suffers the highest amount of loss due to business interruption. The findings of the present study can be used for the improvement of inherent safety and can also be applied to estimate the losses due to fire and explosion.
- انتشار مقاله: 21-02-1398
- نویسندگان: Abbas Sadeghi,Mousa Jabbari Gharabagh,Mohsen Rezaeian,Ali Alidoosti,Davood Eskandari
- مشاهده