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Protective Effect of Distillate and Redistillate of Cow’s Urine in Human Polymorphonuclear Leukocytes Challenged With Established Genotoxic Chemicals 被引量:3
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作者 K.KRISHNAMURTHI DIPANWITA DUTTA +1 位作者 S.D.SIVANESAN T. CHAKRABARTI 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2004年第3期247-256,共10页
Objective From the ancient period cow’urine has been used as a medicine. In Veda, cow’urine was compared to the nectar. In Susrut, several medicinal properties of cow’ urine have been mentioned and are known to ca... Objective From the ancient period cow’urine has been used as a medicine. In Veda, cow’urine was compared to the nectar. In Susrut, several medicinal properties of cow’ urine have been mentioned and are known to cause weight loss, reversal of certain cardiac and kidney problems, indigestion, stomach ache, edema, etc. However, the literature and scripture did not mention the antigenotoxic properties of cow’urine. Methods In the present investigation, the antigenotoxic/ antioxidant properties of cow’ urine distillate and redistillate were studied in vitro. The antioxidant status and volatile fatty acid levels were determined. Actinomycin-D (0.1ol/L) and hydrogen peroxide (150 mol/L) were used for inducing DNA strand break with 0.1% DMSO as negative control. Dose for the antigenotoxic effect of cow’ urine was chosen from the dose response study carried out earlier. Results Both actinomycin-D and H2O2 caused statistically significant DNA unwinding of 80% & 75% respectively (P<0.001) as revealed by fluorimetric analysis of DNA unwinding (FADU), and the damage could be protected with the redistilled cow urine distillate (1, 50 & 100 ) in simultaneous treatment with genotoxic chemicals. Conclusion The redistillate of cowurine was found to possess total antioxidant status of around 2.6 mmol, contributed mainly by volatile fatty acids (1500 mg/L) as revealed by the GC-MS studies. These fatty acids and other antioxidants might cause the observed protective effects. 展开更多
关键词 Ammonia Antioxidants Cow urine distillate Cow urine redistillate Human polymorphonuclear leukocytes (PMNL) DNA damage Fluorimetric analysis of DNA unwinding (FADU) Gas chromatography mass spectrometer (GC-MS) GENOTOXICITY Volatile fatt
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Light olefin production by catalytic co-cracking of Fischer–Tropsch distillate with methanol and the reaction kinetics investigation 被引量:1
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作者 Hui Zou Teng Pan +4 位作者 Yanwen Shi Youwei Cheng Lijun Wang Yu Zhang Xi Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2020年第1期143-151,共9页
Catalytic co-cracking of Fischer–Tropsch(FT) light distillate and methanol combines highly endothermic olefin cracking reaction with exothermic methanol conversion over ZSM-5 catalyst to produce light olefins through... Catalytic co-cracking of Fischer–Tropsch(FT) light distillate and methanol combines highly endothermic olefin cracking reaction with exothermic methanol conversion over ZSM-5 catalyst to produce light olefins through a nearly thermoneutral process. The kinetic behavior of co-cracking reactions was investigated by different feed conditions: methanol feed only, olefin feed only and co-feed of methanol with olefins or F–T distillate. The results showed that methanol converted to C2–C6 olefins in first-order parallel reaction at low space time, methylation and oligomerization–cracking prevailed for the co-feed of methanol and C2–C5 olefins, while for C6–C8 olefins,monomolecular cracking was the dominant reaction whether fed alone or co-fed with methanol. For FT distillate and methanol co-feed, alkanes were almost un-reactive, C3–C5 olefins were obtained as main products, accounting for 71 wt% for all products. A comprehensive co-cracking reaction scheme was proposed and the model parameters were estimated by the nonlinear least square method. It was verified by experimental data that the kinetic model was reliable to predict major product distribution for co-cracking of FT distillate with methanol and could be used for further reactor development and process design. 展开更多
关键词 Fischer–Tropsch distillate CATALYTIC co-cracking Light olefins METHANOL Reaction kinetics
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Anticlastogenic Effect of Redistilled Cow's Urine Distillate in Human Peripheral Lymphocytes Challenged With Manganese Dioxide and Hexavalent Chromium 被引量:1
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作者 DIPANWITA DUTTA S. SARAVANA DEVI +1 位作者 K. KRISHNAMURTHI T. CHAKRABARTI 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2006年第6期487-494,共8页
Objective To study the anticlastogenic effect of redistilled cow's urine distillate (RCUD) in human peripheral lymphocytes (HLC) challenged with manganese dioxide and hexavalent chromium. Methods The anticlastoge... Objective To study the anticlastogenic effect of redistilled cow's urine distillate (RCUD) in human peripheral lymphocytes (HLC) challenged with manganese dioxide and hexavalent chromium. Methods The anticlastogenic activity of redistilled cow's urine distillate was studied in human polymorphonuclear leukocytes (HPNLs) and human peripheral lymphocytes in vitro challenged with manganese dioxide and hexavalent chromium as established genotoxicants and clastogens which could cause induction of DNA strand break, chromosomal aberration and micronucleus. Three different levels of RCUD: 1 μL/mL, 50 μL/mL and 100 μL/mL, were used in the study. Results Manganese dioxide and hexavalent chromium caused statistically significant DNA strand break, chromosomal aberration and micronucleus formation, which could be protected by redisfilled cow's urine distillate. Conclusion The redistilled cow's urine distillate posseses strong anfigenotoxic and antielastogenic properties against HPNLs and HLC treated with Cr^+6 and MnO2. This property is mainly due to the antioxidants present in RCUD. 展开更多
关键词 Redistilled cow's urine distillate (RCUD) DNA strand break CLASTOGENICITY Chromosomal aberration Micronuclei Hexavalent chromium and manganese dioxide
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Modulatory Effect of Distillate of Ocimum sanctum Leaf Extract (Tulsi) on Human Lymphocytes Against Genotoxicants 被引量:1
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作者 DIPANWITA DUTTA S.SARAVANA DEVI +5 位作者 K.KRISHNAMURTHI KOEL KUMAR PRIYANKA VYAS P.L.MUTHAL P.NAOGHARE T.CHAKRABARTI 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2007年第3期226-234,共9页
Objective To study the modulatory effect of distillate of Ocimum sanctum (traditionally known as Tulsi) leaf extract (DTLE) on genotoxicants. Methods In the present investigation, we studied the antigenotoxic and ... Objective To study the modulatory effect of distillate of Ocimum sanctum (traditionally known as Tulsi) leaf extract (DTLE) on genotoxicants. Methods In the present investigation, we studied the antigenotoxic and anticlastogenic effect of distillate of Tulsi leaf extract on (i) human polymorphonuclear leukocytes by evaluating the DNA strand break without metabolic activation against mitomycin C (MMC) and hexavalent chromium (Cr^+6) and (ii) human peripheral lymphocytes (in vitro) with or without metabolic activation against mitomycin C (MMC), hexavalent chromium (Cr^+6) and B[a]P by evaluating chromosomal aberration (CA) and micronucleus assay (MN). Three different doses of DTLE, 50 μL/mL, 100 μL/mL, and 200 μL/mL were selected on the basis of cytotoxicity assay and used for studying DNA strand break, chromosomal aberration and micronucleus emergence. The following positive controls were used for inducing genotoxicity and clastogenicity MMC (0.29 μmol/L) for DNA strand break, chromosomal aberration and 0.51 μmol/L for micronucleus assay; Potassium dichromate (Cr^+6) 600 μmol/L for DNA strand break and 5 μmol/L for chromosomal aberration and micronucleus assay; Benzo[a]pyrene (30 μmol/L) for chromosomal aberration and 40 μmol/L for micronucleus assay. The active ingredients present in the distillate of Tulsi leaf extract were identified by HPLC and LC-MS. Results Mitomycin C (MMC) and hexavalent chromium (Cr^+6) induced statistically significant DNA strand break of respectively 69% and 71% (P〈0.001) as revealed by fluorometric analysis of DNA unwinding. Furthermore, the damage could be protected with DTLE (50 μL/mL, 100 μL/mL, and 200 μL/mL) on simultaneous treatment. Chromosomal aberration and micronucleus formation induced by MMC, Cr^+6 and B[a]P were significantly protected (P〈0.001) by DTLE with and without metabolic activation. Conclusion Distillate of Tulsi leaf extract possesses antioxidants contributed mainly by eugenol, luteolin and apigenin as identified by LC-MS. These active ingredients may have the protective effect against genotoxicants. 展开更多
关键词 distillate of Tulsi leaf extract(DTLE) CYTOTOXICITY DNA strand break Chromosomal aberration(CA) Micronucleus(MN) Hexavalent chromium(Cr^+6) Mitomycin C(MMC) Benzo[a]pyrene(B[a]P)
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Development of Hydrocracking Catalyst to Produce High Quality Clean Middle Distillates
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作者 Zhang Xuejun 1,2 Zhang Zhihua1,2(1. Institute of Daqing Petrochemical Company, Daqing 163714 2. School of Chemistry & Chemical Engineering, University of Petroleum,Dongying 257061) 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2004年第4期19-23,共5页
A novel hydrocracking Ni-W binary catalyst was tentatively designed and prepared by means ofimpregnation on mixed supports of modified Y zeolite and amorphous aluminosilicate . The structure andproperties of catalyst ... A novel hydrocracking Ni-W binary catalyst was tentatively designed and prepared by means ofimpregnation on mixed supports of modified Y zeolite and amorphous aluminosilicate . The structure andproperties of catalyst were extensively characterized by XRD, NH3-TPD, IR and XRF techniques. The perfor-mance of catalyst was evaluated by a 100-ml hydrogenation laboratory test unit with two single-stage fixed-bedreactors connected in series. The characterization results showed that the catalyst has a developed and con-centrated mesopores distribution, suitable acid sites and acid strength distribution, and uniform and highdispersion of metal sites. Under a high conversion rate of 73.8% with the >350℃ feedstock, a 98.1m% of C5+yield and 83.5% of middle distillates selectivity were obtained. The yield of middle distillates boiling between140℃and 370℃ was 68.70m% and its quality could meet the WWFC category III specification. It means thatthis catalyst could be used to produce more high quality clean middle distillates derived from heavy oilhydrocracking. The potential aromatic content of heavy naphtha from 65℃ to 140℃ was 37.5m%. The BMCIvalue of >370℃ tail oil was 6.6. The heavy naphtha and tail oil are premium feedstocks for catalytic reformingand steam cracker units. 展开更多
关键词 HYDROCRACKING NI-W binary catalyst CLEAN MIDDLE distillate WWFC category specification
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Attenuation of Carbon Tetrachloride-Induced Hepatotoxicity by Cow Urine Distillate in Rats
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作者 M P GURURAJA A B JOSHI +3 位作者 HIMANSHU JOSHI D SATHYANARAYANA E V S SUBRAHMANYAM K S CHANDRASHEKHAR 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2009年第4期345-347,共3页
Objective To study the carbon tetrachloride-induced hepatoprotective activity in cow urine. Methods Effect of cow urine distillate on liver function was studied in vivo in rats intoxicated with carbon tetrachloride (... Objective To study the carbon tetrachloride-induced hepatoprotective activity in cow urine. Methods Effect of cow urine distillate on liver function was studied in vivo in rats intoxicated with carbon tetrachloride (CC14). Hepatotoxicity was induced by a 1 : 1 (v/v) mixture of CCl4 in olive oil (5 mL/kg i.p). Protective effect of cow urine distillate (in three dose levels) and standard drug Silymarin (100 mg/kg, p.o) on liver function were studied in intoxicated rats. Parameters in the study included liver function tests and histological observations. Results The cow urine distillate decreased the levels of SGOT, SGPT, ALP, GGT, and total bilirubin in a dose-dependent manner (P〈0.05) as sylimarin. Conclusion The observed protective effects of cow urine distillate on liver function might be due to the presence of antioxidants in cow urine. 展开更多
关键词 HEPATOTOXICITY Cow urine distillate CCl4 SILYMARIN
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Effects of Tocols Rich Fraction Isolated from Rice Bran Oil Deodorizer Distillate on Plasma and Hepatic Lipid Concentrations in Rats
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作者 Tina A. Gomes Xuan Gu +3 位作者 Cindi R. Brownmiller Luke Howard Cesar M. Compadre Sun-Ok Lee 《Journal of Biosciences and Medicines》 2015年第9期1-8,共8页
A great deal of attention has been focused on the potential health benefits of using rice bran oil because it is a rich source of bioactive compounds. Rice bran oil deodorizer distillate (RBODD) is a byproduct obtaine... A great deal of attention has been focused on the potential health benefits of using rice bran oil because it is a rich source of bioactive compounds. Rice bran oil deodorizer distillate (RBODD) is a byproduct obtained from distillation of rice bran oil. Elevated plasma cholesterol level is one of the major risk factors for coronary heart disease. The objective of this study was to investigate the effects of tocols (tocopherols + tocotrienols) rich fraction isolated from RBODD on plasma and liver lipid concentrations in rats. Male Sprague Dawley rats (6 weeks of age) were randomly assigned into three groups: normal fat control (NFC), high fat control (HFC) and high fat diet plus tocols rich fraction (RBODD). RBODD was administered daily for 3 weeks by oral gavage using 5% of Tween-80 as a vehicle. The rats in the control groups received 5% of Tween-80 alone in the same manner. Blood samples and livers were collected at the end of the feeding period. RBODD group had significantly lower plasma triglyceride levels compared to the HFC group (p < 0.05). However, no significant changes for plasma total and lipoprotein cholesterol levels were found in RBODD compared with HFC. Compared to the rat fed HFC, hepatic free fatty acids were significantly reduced in the rats with the RBODD treatment (p < 0.05). The results suggest that the tocols rich fraction isolated from RBODD is associated with decreased plasma triglyceride and hepatic free fatty acids concentrations. Further study is needed to investigate the mechanism and optimal dose by which isomers of tocols lower triglyceride concentrations. 展开更多
关键词 Rice BRAN Oil DEODORIZER distillate Tocols Oral GAVAGE TRIGLYCERIDES
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The Effect of Fatty Acid Methyl Esters and Hydrogenated Vegetable Oils on Oxidation Stability,Cold Properties and Lubricity of Marine Distillate Fuels
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作者 Theodora Tyrovola George Dodos Fanourios Zannikos 《Journal of Environmental Science and Engineering(A)》 2018年第7期274-284,共11页
Shipping plays a vital role in the world economy.Around 90%of the world's trade is transported by ship in a cost-effective and reliable manner.Global shipping is responsible for 2-3%of the total global CO2 emissio... Shipping plays a vital role in the world economy.Around 90%of the world's trade is transported by ship in a cost-effective and reliable manner.Global shipping is responsible for 2-3%of the total global CO2 emissions.In addition,shipping accounts for up to 4-9%of all sulphur,and 10-15%of all nitrous oxide emissions.Without taking any measures,these emissions would more than double as seaborne trade is expected to further grow from 30 billion tone miles in 2006 to more than 100 billion in 2050.To counter these emissions the international community has developed frameworks for energy efficiency measures,as well as emission reduction targets for SOx and NOx in appointed ECAs(Emission Control Areas).Biofuels satisfy fully or partially the new emission regulations and sulfur limits without compromising the economy.The goal of this work is to study and evaluate the physicochemical properties of conventional marine distillate fuel and its blends with renewable-alternative fuels(UCOME(Used Cooking Oils Methyl Esters)and HVO(Hydrogenated Vegetable Oils)). 展开更多
关键词 MARINE FUEL distillate FUEL biofuels ECAS emission reduction
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Effect of Bio-Disc on Distillate Yield and Crude Oil Properties
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作者 Anthony Kerunwa Princewill O. Ariche 《World Journal of Engineering and Technology》 2020年第3期367-381,共15页
The market worth of the crude oil transported to the international market has a great influence on the crude’s physical properties, as such demands that certain desirable physical properties ought to be possessed. Th... The market worth of the crude oil transported to the international market has a great influence on the crude’s physical properties, as such demands that certain desirable physical properties ought to be possessed. The distillation of crude oil is the first process in the sequence of refining operation and is key to refinery operations profitability. In this work, five crude oil samples were collected from a reservoir in the Niger Delta designated as S11A, S12A, S13A, S14A and S15A. Sample S11A was not treated with bio</span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;">disc while samples S12A-S15A were treated with bio</span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;">disc at different number of times. This was necessary to ascertain the effect of the bio</span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;">disc on crude oil physical properties and their distillate yield. After the treatment, the specific gravity, American Petroleum Institute (API), pour point, flash point and viscosity of the treated and untreated crude samples were determined and then the samples distilled with a distillation tester. From the results obtained, the bio</span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;">disc had </span><span style="font-family:Verdana;">a </span><span style="font-family:Verdana;">great influence on the physical properties of the samples as well as on the distillate yield. The specific gravities of the oil samples decreased as the number of times the samples were treated with bio</span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;">disc increases and this in turn increased the crudes’ API. The pourpoint and viscosity decreased with increase in number of treatments of crude samples with bio-disc. As the number of treatments increased, the crude samples which were originally paraffinic were tending towards being naphthenic. The flash point and distillate yield increased with increase in number of treatments of crude samples with bio</span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;">disc. Thus, treatment of crude oil with bio</span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;">dic alters the physical properties of the crude</span><span style="font-family:Verdana;">. 展开更多
关键词 HYDROCARBON Flash Point Specific Gravity REFINING Viscosity DISTILLATION Petroleum Products
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Valorization of sustainable vegetable oil deodorizer distillate as a novel fatliquor
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作者 El-Shahat H.A.Nashy Adel Gabr Abdel-Razek +2 位作者 Minar Mahmoud M.Hassanein Ghada A.Abo-Elwafa Hamed Elsayed 《Collagen and Leather》 EI CAS 2023年第3期60-72,共13页
The deodorizer distillate(DD)is a byproduct of vegetable oil processing industry and is rich in functional bioactive components.This study aimed to employ phosphorylation modification for DD to produce a new sustainab... The deodorizer distillate(DD)is a byproduct of vegetable oil processing industry and is rich in functional bioactive components.This study aimed to employ phosphorylation modification for DD to produce a new sustainable fatliquor.The bioactive ingredients in DD,namely fatty acids,sterols,and tocopherols,were determined by using HPLC and GLC.The results revealed that the DD sample contained a high percentage of unsaturated fatty acids(72.3%)and high levels ofγandδ-tocopherols(54.8%and 31.60%,respectively).Mechanical parameters(tensile strength,elongation at break,and tear strength)of leather were improved after being treated with the prepared fatliquor emulsion.Eventually,SEM showed that the texture of the fatliquored leather had been remarkably enhanced.Moreover,the fatliquored leather possessed effective antibacterial effect against the specified+ve,-ve bacteria,and Candida albicans microorganisms.The strength,fullness,soft handle,and elasticity of leather were all improved,and the grain of leather was protected from becoming loose after drying. 展开更多
关键词 Vegetable oil Deodorizer distillate Bioactive components FATLIQUOR PHOSPHORYLATION Chrome tanned leather
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A Real-time Prediction System for Molecular-level Information of Heavy Oil Based on Machine Learning
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作者 Yuan Zhuang Wang Yuan +8 位作者 Zhang Zhibo Yuan Yibo Yang Zhe Xu Wei Lin Yang Yan Hao Zhou Xin Zhao Hui Yang Chaohe 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2024年第2期121-134,共14页
Acquiring accurate molecular-level information about petroleum is crucial for refining and chemical enterprises to implement the“selection of the optimal processing route”strategy.With the development of data predic... Acquiring accurate molecular-level information about petroleum is crucial for refining and chemical enterprises to implement the“selection of the optimal processing route”strategy.With the development of data prediction systems represented by machine learning,it has become possible for real-time prediction systems of petroleum fraction molecular information to replace analyses such as gas chromatography and mass spectrometry.However,the biggest difficulty lies in acquiring the data required for training the neural network.To address these issues,this work proposes an innovative method that utilizes the Aspen HYSYS and full two-dimensional gas chromatography-time-of-flight mass spectrometry to establish a comprehensive training database.Subsequently,a deep neural network prediction model is developed for heavy distillate oil to predict its composition in terms of molecular structure.After training,the model accurately predicts the molecular composition of catalytically cracked raw oil in a refinery.The validation and test sets exhibit R2 values of 0.99769 and 0.99807,respectively,and the average relative error of molecular composition prediction for raw materials of the catalytic cracking unit is less than 7%.Finally,the SHAP(SHapley Additive ExPlanation)interpretation method is used to disclose the relationship among different variables by performing global and local weight comparisons and correlation analyses. 展开更多
关键词 heavy distillate oil molecular composition deep learning SHAP interpretation method
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Enhancement of distillate output of double basin solar still with vacuum tubes 被引量:3
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作者 Hitesh N PANCHAL P K SHAH 《Frontiers in Energy》 SCIE CSCD 2014年第1期101-109,共9页
The latent heat of condensation is lost to the atmosphere; hence it is not utilized to increase distillate output of single basin solar stills. This difficulty was overcome by attaching an additional basin to the main... The latent heat of condensation is lost to the atmosphere; hence it is not utilized to increase distillate output of single basin solar stills. This difficulty was overcome by attaching an additional basin to the main basin. The performance of the double basin solar still was also increased by attaching vacuum tubes to the lower basin; hence the lower basin possessed a higher tempera- ture throughout the day. The latent heat of condensation of the bottom basin was also utilized to increase distillate. But the distillate output of the compared with that of the proposed a novel approach to of the double basin solar still top basin was even lower bottom basin. This paper increase the distillate output attached with vacuum tubes by introducing different sensible energy storage materials like pebbles, black granite gravel and calcium stones to increase the basin area. Experiments were conducted in climate conditions of Mehsana (23.6000° N, 72.4000° E) Gujarat from April to September 2013 with a constant water depth of 2 cm in the top basin with and without the use of basin materials. The results showed that the distillate output of basin material with calcium stones is greater (74%) compared with that of black granite gravel and pebbles. The integration of vacuum tubes with solar still greatly increases the distillate output of the solar still by providing hot water at the lower basin. 展开更多
关键词 double basin solar still calcium stones pebbles granite gravel distillate output
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Environmental,economic and exergy analysis of separation of ternary azeotrope by variable pressure extractive distillation based on multi-objective optimization
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作者 Peizhe Cui Jiafu Xing +5 位作者 Chen Li Mengjin Zhou Jifu Zhang Yasen Dai Limei Zhong Yinglong Wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第1期145-157,共13页
In this work,the ternary azeotrope of tert-butyl alcohol/ethyl acetate/water is separated by extractive distillation(ED)to recover the available constituents and protect the environment.Based on the conductor like shi... In this work,the ternary azeotrope of tert-butyl alcohol/ethyl acetate/water is separated by extractive distillation(ED)to recover the available constituents and protect the environment.Based on the conductor like shielding model and relative volatility method,ethylene glycol was selected as the extractant in the separation process.In addition,in view of the characteristic that the relative volatility between components changes with pressure,the multi-objective optimization method based on nondominated sorting genetic algorithm II optimizes the pressure and the amount of solvent cooperatively to avoid falling into the optimal local solution.Based on the optimal process parameters,the proposed heat-integrated process can reduce the gas emissions by 29.30%.The heat-integrated ED,further coupled with the pervaporation process,can reduce gas emission by 42.36%and has the highest exergy efficiency of 47.56%.In addition,based on the heat-integrated process,the proposed two heat pump assisted heat-integrated ED processes show good economic and environmental performance.The double heat pump assisted heat-integrated ED can reduce the total annual cost by 28.78%and the gas emissions by 55.83%compared with the basis process,which has a good application prospect.This work provides a feasible approach for the separation of ternary azeotropes. 展开更多
关键词 Extractive distillation Optimization MIXTURES SEPARATION
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Cascade equilibrium stage relaxation method by introducing equilibrium efficiency parameter
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作者 Xuepu Cao Shengkun Jia +2 位作者 Xing Qian Yiqing Luo Xigang Yuan 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第2期145-156,共12页
Optimizing multistage processes,such as distillation or absorption,is a complex mixed-integer nonlinear programming(MINLP)problem.Relaxing integer into continuous variables and solving the easier nonlinear programming... Optimizing multistage processes,such as distillation or absorption,is a complex mixed-integer nonlinear programming(MINLP)problem.Relaxing integer into continuous variables and solving the easier nonlinear programming(NLP)problem is an optimization idea for the multistage process.In this article,we propose a relaxation method based on the efficiency parameter.When the efficiency parameter is 1or 0,the proposed model is equivalent to the complete existence or inexistence of the equilibrium stage.And non-integer efficiency represents partial existence.A multi-component absorption case shows a natural penalty for non-integer efficiency,which can assist the efficiency parameter converging to 0 or 1.However,its penalty is weaker than the existing relaxation models,such as the bypass efficiency model.In a simple distillation case,we show that this property can weaken the nonconvexity of the optimization problem and increase the probability of obtaining better optimization results. 展开更多
关键词 Mathematical modeling ABSORPTION DISTILLATION Optimization
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LDAS&ET-AD:Learnable Distillation Attack Strategies and Evolvable Teachers Adversarial Distillation
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作者 Shuyi Li Hongchao Hu +3 位作者 Xiaohan Yang Guozhen Cheng Wenyan Liu Wei Guo 《Computers, Materials & Continua》 SCIE EI 2024年第5期2331-2359,共29页
Adversarial distillation(AD)has emerged as a potential solution to tackle the challenging optimization problem of loss with hard labels in adversarial training.However,fixed sample-agnostic and student-egocentric atta... Adversarial distillation(AD)has emerged as a potential solution to tackle the challenging optimization problem of loss with hard labels in adversarial training.However,fixed sample-agnostic and student-egocentric attack strategies are unsuitable for distillation.Additionally,the reliability of guidance from static teachers diminishes as target models become more robust.This paper proposes an AD method called Learnable Distillation Attack Strategies and Evolvable Teachers Adversarial Distillation(LDAS&ET-AD).Firstly,a learnable distillation attack strategies generating mechanism is developed to automatically generate sample-dependent attack strategies tailored for distillation.A strategy model is introduced to produce attack strategies that enable adversarial examples(AEs)to be created in areas where the target model significantly diverges from the teachers by competing with the target model in minimizing or maximizing the AD loss.Secondly,a teacher evolution strategy is introduced to enhance the reliability and effectiveness of knowledge in improving the generalization performance of the target model.By calculating the experimentally updated target model’s validation performance on both clean samples and AEs,the impact of distillation from each training sample and AE on the target model’s generalization and robustness abilities is assessed to serve as feedback to fine-tune standard and robust teachers accordingly.Experiments evaluate the performance of LDAS&ET-AD against different adversarial attacks on the CIFAR-10 and CIFAR-100 datasets.The experimental results demonstrate that the proposed method achieves a robust precision of 45.39%and 42.63%against AutoAttack(AA)on the CIFAR-10 dataset for ResNet-18 and MobileNet-V2,respectively,marking an improvement of 2.31%and 3.49%over the baseline method.In comparison to state-of-the-art adversarial defense techniques,our method surpasses Introspective Adversarial Distillation,the top-performing method in terms of robustness under AA attack for the CIFAR-10 dataset,with enhancements of 1.40%and 1.43%for ResNet-18 and MobileNet-V2,respectively.These findings demonstrate the effectiveness of our proposed method in enhancing the robustness of deep learning networks(DNNs)against prevalent adversarial attacks when compared to other competing methods.In conclusion,LDAS&ET-AD provides reliable and informative soft labels to one of the most promising defense methods,AT,alleviating the limitations of untrusted teachers and unsuitable AEs in existing AD techniques.We hope this paper promotes the development of DNNs in real-world trust-sensitive fields and helps ensure a more secure and dependable future for artificial intelligence systems. 展开更多
关键词 Adversarial training adversarial distillation learnable distillation attack strategies teacher evolution strategy
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Energy-saving design and optimization of pressure-swing-assisted ternary heterogenous azeotropic distillations
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作者 Lianjie Wu Kun Lu +3 位作者 Qirui Li Lianghua Xu Yiqing Luo Xigang Yuan 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第4期1-7,共7页
A huge amount of energy is always consumed to separate the ternary azeotropic mixtures by distillations.The heterogeneous azeotropic distillation and the pressure-swing distillation are two kinds of effective technolo... A huge amount of energy is always consumed to separate the ternary azeotropic mixtures by distillations.The heterogeneous azeotropic distillation and the pressure-swing distillation are two kinds of effective technologies to separate heterogeneous azeotropes without entrainer addition.To give better play to the synergistic energy-saving effect of these two processes,a novel pressure-swing-assisted ternary heterogeneous azeotropic distillation(THAD)process is proposed firstly.In this process,the ternary heterogeneous azeotrope is decanted into two liquid phases before being refluxed into the azeotropic distillation column to avoid the aqueous phase remixing,and three columns'pressures are modified to decrease the flowrates of the recycle streams.Then the dividing wall column and heat integration technologies are introduced to further reduce its energy consumption,and the pressureswing-assisted ternary heterogeneous azeotropic dividing-wall column and its heat integration structure are achieved.A genetic algorithm procedure is used to optimize the proposed processes.The design results show that the proposed processes have higher energy efficiencies and lower CO_(2)emissions than the published THAD process. 展开更多
关键词 DISTILLATION SEPARATION Process control Process systems
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Process synthesis for the separation of coal-to-ethanol products
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作者 Qingping Qu Daoyan Liu +1 位作者 Hao Lyu Jinsheng Sun 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第5期263-278,共16页
The coal-to-ethanol process,as the clean coal utilization,faces challenges from the energy-intensive distillation that separates multi-component effluents for pure ethanol.Referring to at least eight columns,the synth... The coal-to-ethanol process,as the clean coal utilization,faces challenges from the energy-intensive distillation that separates multi-component effluents for pure ethanol.Referring to at least eight columns,the synthesis of the ethanol distillation system is impracticable for exhaustive comparison and difficult for conventional superstructure-based optimization as rigorous models are used.This work adopts a superstructure-based framework,which combines the strategy that adaptively selects branches of the state-equipment network and the parallel stochastic algorithm for process synthesis.High-performance computing significantly reduces time consumption,and the adaptive strategy substantially lowers the complexity of the superstructure model.Moreover,parallel computing,elite search,population redistribution,and retention strategies for irrelevant parameters are used to improve the optimization efficiency further.The optimization terminates after 3000 generations,providing a flowsheet solution that applies two non-sharp splitting options in its distillation sequence.As a result,the 59-dimension superstructure-based optimization was solved efficiently via a differential evolution algorithm,and a high-quality solution with a 28.34%lower total annual cost than the benchmark was obtained.Meanwhile,the solution of the superstructure-based optimization is comparable to that obtained by optimizing a single specific configuration one by one.It indicates that the superstructure-based optimization that combines the adaptive strategy can be a promising approach to handling the process synthesis of large-scale and complex chemical processes. 展开更多
关键词 Coal-to-ethanol Process synthesis Superstructure-based optimization Differential evolution algorithm DISTILLATION
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Learning Epipolar Line Window Attention for Stereo Image Super-Resolution Reconstruction
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作者 Xue Li Hongying Zhang +1 位作者 Zixun Ye Xiaoru 《Computers, Materials & Continua》 SCIE EI 2024年第2期2847-2864,共18页
Transformer-based stereo image super-resolution reconstruction(Stereo SR)methods have significantly improved image quality.However,existing methods have deficiencies in paying attention to detailed features and do not... Transformer-based stereo image super-resolution reconstruction(Stereo SR)methods have significantly improved image quality.However,existing methods have deficiencies in paying attention to detailed features and do not consider the offset of pixels along the epipolar lines in complementary views when integrating stereo information.To address these challenges,this paper introduces a novel epipolar line window attention stereo image super-resolution network(EWASSR).For detail feature restoration,we design a feature extractor based on Transformer and convolutional neural network(CNN),which consists of(shifted)window-based self-attention((S)W-MSA)and feature distillation and enhancement blocks(FDEB).This combination effectively solves the problem of global image perception and local feature attention and captures more discriminative high-frequency features of the image.Furthermore,to address the problem of offset of complementary pixels in stereo images,we propose an epipolar line window attention(EWA)mechanism,which divides windows along the epipolar direction to promote efficient matching of shifted pixels,even in pixel smooth areas.More accurate pixel matching can be achieved using adjacent pixels in the window as a reference.Extensive experiments demonstrate that our EWASSR can reconstruct more realistic detailed features.Comparative quantitative results show that in the experimental results of our EWASSR on the Middlebury and Flickr1024 data sets for 2×SR,compared with the recent network,the Peak signal-to-noise ratio(PSNR)increased by 0.37 dB and 0.34 dB,respectively. 展开更多
关键词 Stereo SR epipolar line window attention feature distillation
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Miscibility of light oil and flue gas under thermal action
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作者 XI Changfeng WANG Bojun +7 位作者 ZHAO Fang HUA Daode QI Zongyao LIU Tong ZHAO Zeqi TANG Junshi ZHOU You WANG Hongzhuang 《Petroleum Exploration and Development》 SCIE 2024年第1期164-171,共8页
The miscibility of flue gas and different types of light oils is investigated through slender-tube miscible displacement experiment at high temperature and high pressure.Under the conditions of high temperature and hi... The miscibility of flue gas and different types of light oils is investigated through slender-tube miscible displacement experiment at high temperature and high pressure.Under the conditions of high temperature and high pressure,the miscible displacement of flue gas and light oil is possible.At the same temperature,there is a linear relationship between oil displacement efficiency and pressure.At the same pressure,the oil displacement efficiency increases gently and then rapidly to more than 90% to achieve miscible displacement with the increase of temperature.The rapid increase of oil displacement efficiency is closely related to the process that the light components of oil transit in phase state due to distillation with the rise of temperature.Moreover,at the same pressure,the lighter the oil,the lower the minimum miscibility temperature between flue gas and oil,which allows easier miscibility and ultimately better performance of thermal miscible flooding by air injection.The miscibility between flue gas and light oil at high temperature and high pressure is more typically characterized by phase transition at high temperature in supercritical state,and it is different from the contact extraction miscibility of CO_(2) under conventional high pressure conditions. 展开更多
关键词 light oil flue gas flooding thermal miscible flooding miscible law distillation phase transition minimum miscible pressure minimum miscible temperature
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A Novel Tensor Decomposition-Based Efficient Detector for Low-Altitude Aerial Objects With Knowledge Distillation Scheme
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作者 Nianyin Zeng Xinyu Li +2 位作者 Peishu Wu Han Li Xin Luo 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第2期487-501,共15页
Unmanned aerial vehicles(UAVs) have gained significant attention in practical applications, especially the low-altitude aerial(LAA) object detection imposes stringent requirements on recognition accuracy and computati... Unmanned aerial vehicles(UAVs) have gained significant attention in practical applications, especially the low-altitude aerial(LAA) object detection imposes stringent requirements on recognition accuracy and computational resources. In this paper, the LAA images-oriented tensor decomposition and knowledge distillation-based network(TDKD-Net) is proposed,where the TT-format TD(tensor decomposition) and equalweighted response-based KD(knowledge distillation) methods are designed to minimize redundant parameters while ensuring comparable performance. Moreover, some robust network structures are developed, including the small object detection head and the dual-domain attention mechanism, which enable the model to leverage the learned knowledge from small-scale targets and selectively focus on salient features. Considering the imbalance of bounding box regression samples and the inaccuracy of regression geometric factors, the focal and efficient IoU(intersection of union) loss with optimal transport assignment(F-EIoU-OTA)mechanism is proposed to improve the detection accuracy. The proposed TDKD-Net is comprehensively evaluated through extensive experiments, and the results have demonstrated the effectiveness and superiority of the developed methods in comparison to other advanced detection algorithms, which also present high generalization and strong robustness. As a resource-efficient precise network, the complex detection of small and occluded LAA objects is also well addressed by TDKD-Net, which provides useful insights on handling imbalanced issues and realizing domain adaptation. 展开更多
关键词 Attention mechanism knowledge distillation(KD) object detection tensor decomposition(TD) unmanned aerial vehicles(UAVs)
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