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Antipyretic and anticonvulsant activity of n-hexane fraction of viola betonicifolia
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作者 Naveed Muhammad Muhammad Saeed +2 位作者 Haroon Khan Naila Raziq Syed Muhammad Ashhad Halimi 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2013年第4期280-283,共4页
Objective:To investigate the antipyretic and anticonvulsant activities of n-hexane fraction of Viola betonicifolia(V.betonicifolia).Methods:The antipyretic effect was scrutinized using brewer's yeast induced pyrex... Objective:To investigate the antipyretic and anticonvulsant activities of n-hexane fraction of Viola betonicifolia(V.betonicifolia).Methods:The antipyretic effect was scrutinized using brewer's yeast induced pyrexia and anticonvlsion effect was tested using pentylenetetrazol and strychnine induced convulsion in mice.Results:N-hexane fraction of V.betonicifolia demonstrated highly significant antipyretic activity during various assessment times(1-5 h)when challenged in yeast induced pyrexia test.The effect was in a dose dependent manner with maximum attenuation(82.50%)observed at 300 mg/kg i.p.When tested in pentylenetetrazol induced convulsion test,the 1st stage(Ear and facial twitching)and 2nd stage(Convulsive wave through the body)was 100%protected during 24 h at all the test doses(300,400 and 500 mg/kg i.p.),while the latency time of remaining stages was significantly increased.The maximum effect was observed by n-hexane fraction of V.betonicifolia at 400 and 500 mg/kg i.p.,as the latency time for generalized clonic-tonic seizure(5th stage)was increased up to 25.34 min.However,n-hexane fraction of V.betonicifolia had no protection in strychnine induced convulsion test.Conclusions:In conclusion,phytopharmacological studies provide scientific foundation to the folk uses of the plant in the treatment of pyrexia and neurological disorders. 展开更多
关键词 VIOLA betonicifolia n-hexane fraction ANTIPYRETIC ANTICONVULSANT
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GC/MS analyses of fractionated extraction of Shenfu coal with CS2,n-hexane,benzene 被引量:2
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作者 王晓华 魏贤勇 《Journal of Coal Science & Engineering(China)》 2008年第4期672-674,共3页
Shenfu coal was extracted with 0S2, n-hexane, benzene sequentially. The extracts were analyzed with GC/MS. It is presented that group seperation of soluble organic compounds in the coal can be achieved by fractionated... Shenfu coal was extracted with 0S2, n-hexane, benzene sequentially. The extracts were analyzed with GC/MS. It is presented that group seperation of soluble organic compounds in the coal can be achieved by fractionated extraction using different solvents. Main components in CS2 soluble fraction from Shenfu coal are alkyl-substituted arenes. Aliphatic hydrocarbons are overwhelmingly predominant in n-hexane-soluble fraction. Dito tricyclic aramatic hydrocarbons are identified in benzene-soluble fraction. The molecular structures detection of 2, 4, 6-trichlorobenzenamine and 3, 3', 4, 4', 5, 5'-hexachloro-1, 1'- biphenyl and 2-chlorocyclohexanol firstly provide information for existence form of chlorine in coal. 展开更多
关键词 solvent fractionated extraction chemical constituent GC/MS
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Efficient prediction of gaseous n-hexane removal in two-phase partitioning bioreactors with silicone oil based on the mechanism and kinetic models
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作者 Lichao Lu Tuo Ju +6 位作者 Yangdan Fang Jingtao Hu Zhuqiu Sun Zhuowei Cheng Qian Li Jianmeng Chen Dong-zhi Chen 《Journal of Environmental Sciences》 2025年第8期729-740,共12页
Two-phase partitioning bioreactors(TPPBs)have been widely used because they overcome the mass-transfer limitation of hydrophobic volatile organic compounds(VOCs)in waste gas biological treatments.Understanding the mec... Two-phase partitioning bioreactors(TPPBs)have been widely used because they overcome the mass-transfer limitation of hydrophobic volatile organic compounds(VOCs)in waste gas biological treatments.Understanding the mechanisms of mass-transfer enhancement in TPPBs would enable efficient predictions for further industrial applications.In this study,influences of gradually increasing silicone oil ratio on the TPPB was explored,and a 94.35%reduction of the n-hexane partition coefficient was observed with 0.1 vol.%silicone,which increased to 80.7%along with a 40-fold removal efficiency enhancement in the stabilised removal period.The elimination capacity increased from 1.47 to 148.35 g/(m^(3)·h),i.e.a 101-fold increase compared with that of the single-phase reactors,when 10 vol.%(3 Critical Micelle Concentration)silicone oil was added.The significantly promoted partition coefficient was the main reason for the mass transfer enhancement,which covered the negative influences of the decreased total mass-transfer coefficient with increasing silicone oil volume ratio.The gradually rising stirring rate was benefit to the n-hexane removal,which became negative when the dominant resistance shifted from mass transfer to biodegradation.Moreover,a mass-transfer-reaction kinetic model of the TPPB was constructed based on the balance of n-hexane concentration,dissolved oxygen and biomass.Similar to the mechanism,the partition factor was predicted sensitive to the removal performance,and another five sensitive parameters were found simultaneously.This forecasting method enables the optimisation of TPPB performance and provides theoretical support for hydrophobic VOCs degradation. 展开更多
关键词 Mass transfer n-hexane Two-phase partitioning bioreactors Silicone oil
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A Fractional-Order Study for Bicomplex Haemorrhagic Infection in Several Populations Conditions
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作者 Muhammad Farman Muhammad Hashir Zubair +2 位作者 Hua Li Kottakkaran Sooppy Nisar Mohamad Hafez 《Computer Modeling in Engineering & Sciences》 2026年第1期926-953,共28页
Lassa Fever(LF)is a viral hemorrhagic illness transmitted via rodents and is endemic in West Africa,causing thousands of deaths annually.This study develops a dynamic model of Lassa virus transmission,capturing the pr... Lassa Fever(LF)is a viral hemorrhagic illness transmitted via rodents and is endemic in West Africa,causing thousands of deaths annually.This study develops a dynamic model of Lassa virus transmission,capturing the progression of the disease through susceptible,exposed,infected,and recovered populations.The focus is on simulating this model using the fractional Caputo derivative,allowing both qualitative and quantitative analyses of boundedness,positivity,and solution uniqueness.Fixed-point theory and Lipschitz conditions are employed to confirm the existence and uniqueness of solutions,while Lyapunov functions establish the global stability of both disease-free and endemic equilibria.The study further examines the role of the Caputo operator by solving the generalized power-law kernel via a two-step Lagrange polynomial method.This approach offers practical advantages in handling additional data points in integral forms,though Newton polynomial-based schemes are generally more accurate and can outperform Lagrange-based Adams-Bashforth methods.Graphical simulations validate the proposed numerical approach for different fractional orders(ν)and illustrate the influence of model parameters on disease dynamics.Results indicate that increasing the fractional order accelerates the decline of Lassa fever in both human and rodent populations.Moreover,fractional-order modeling provides more nuanced insights than traditional integer-order models,suggesting potential improvements for medical intervention strategies.The study demonstrates that carefully chosen fractional orders can optimize convergence and enhance the predictive capacity of Lassa fever models,offering a promising direction for future research in epidemiological modeling. 展开更多
关键词 Lassa fever mathematical model caputo fractional operator lyapunov stability
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CT-derived fractional flow reserve combined with atherosclerotic extent to determine long-term outcomes in diabetic patients with coronary artery disease
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作者 Zhi-Qiang WANG Zhen-Nan LI +1 位作者 Zhi-Hui HOU Bin LU 《Journal of Geriatric Cardiology》 2026年第1期27-35,共9页
Background There is still limited data on predictive value of coronary computed tomography angiography(CCTA)–derived fractional flow reserve(CT-FFR) for long term outcomes. We examined the long-term prognostic value ... Background There is still limited data on predictive value of coronary computed tomography angiography(CCTA)–derived fractional flow reserve(CT-FFR) for long term outcomes. We examined the long-term prognostic value of CT-FFR combined with CCTA–defined atherosclerotic extent in diabetic patients with coronary artery disease(CAD).Methods A retrospective pooled analysis of individual patient data was performed. Deep-learning-based vessel-specific CTFFR was calculated. All patients enrolled were followed-up for at least 5 years. Predictive abilities for major adverse cardiac events(MACE) were compared among three models(model 1), constructed using clinical variables;model 2, model 1+CCTA–derived atherosclerotic extent(Leiden risk score);and model 3, model 2+CT-FFR.Results A total of 480 diabetic patients [median age, 61(55–66) years;52.9% men] were included. During a median follow-up time of 2197(2126–2355) days, 55 patients(11.5%) experienced MACE. In multivariate-adjusted Cox models, Leiden risk score(HR: 1.06;95% CI: 1.01–1.11;P = 0.013) and CT-FFR ≤ 0.80(HR: 6.54;95% CI: 3.18–13.45;P < 0.001) were the independent predictors. The discriminant ability was higher in model 2 than in model 1(C-index, 0.75 vs. 0.63;P < 0.001) and was further promoted by adding CT-FFR to model 3(C-index, 0.81 vs. 0.75;P = 0.002). Net reclassification improvement(NRI) was 0.19(P = 0.009) for model 2 beyond model 1. Of note, adding CT-FFR to model 3 also exhibited significantly improved reclassification compared with model 2(NRI = 0.14;P = 0.011).Conclusion In diabetic patients with CAD, CT-FFR provides robust and incremental prognostic information for predicting longterm outcomes. The combined model exhibits improved prediction abilities, which is beneficial for risk stratification. 展开更多
关键词 fractional flow reserve ct ffr coronary artery disease cad methods tomography angiography ccta derived coronary artery disease atherosclerotic extent fractional flow reserve diabetic patients coronary computed tomography angiography
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Land use type shapes carbon pathways in Tibetan alpine ecosystems:Characterization of ^(13)C abundance in aggregates and density fractions
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作者 Xin Wan Dangjun Wang +7 位作者 Junya Li Shuaiwen Zhang Linyang Li Minghui He Zhiguo Li Hao Jiang Peng Chen Yi Liu 《Journal of Integrative Agriculture》 2026年第2期448-459,共12页
Insight into the carbon turnover in soil aggregates and density fractions is essential for reducing the uncertainty in estimating carbon pools on the Tibetan Plateau,and how they vary with land use type is unclear.In ... Insight into the carbon turnover in soil aggregates and density fractions is essential for reducing the uncertainty in estimating carbon pools on the Tibetan Plateau,and how they vary with land use type is unclear.In this study,the effect of land use type on carbon storage and fractionation was quantified based on organic carbon and its ^(13)C abundance at the microscale of soil aggregates and density fractions in Tibetan alpine ecosystems.The sequence of soil aggregate destruction in the land use types of plantation(13.1%)<shrubland(32.7%)<grassland(47.9%)<farmland(61.8%)shows that plantations strengthen the soil structure.Plantation land had a greater contribution of light fraction organic carbon(28.3%)but a lower contribution of mineral-associated organic carbon(40.6%)to the carbon stock compared to farmland(13.5 and 70.3%).Interestingly,plantation land enhanced the aggregational differentiation of organic carbon and ^(13)C in each density fraction,whereas no such phenomenon existed in the soil organic carbon.Carbon isotope analyses revealed that carbon transfer in the plantation land occurred from the light fraction in macroaggregates(–24.9‰)to the mineral-associated fraction in microaggregates(–19.9‰).When compared to the other three land use types,the low transferability of carbon in aggregates and density fractions in plantation land provides a stable carbon pool for the Tibetan Plateau.This study shows that plantations can mitigate global climate change by slowing carbon transfer and increasing carbon storage at the microscale of aggregates and density fractions in alpine regions. 展开更多
关键词 land use type soil aggregate density fractions carbon transfer Tibetan Plateau
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The Immunomodulatory,Anti-Tumor,and Metabolic Regulatory Effects of Fraction D of Polysaccharide from Grifola frondosa:Clinical Experiments and Mechanistic Insights
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作者 Nurfarih Hanna Mohd Zarif Fikri Bin Mohd +1 位作者 Muhammad Nabil Fikri Bin Mohd Nurfarazuna Binti Mohd Fadrol 《Proceedings of Anticancer Research》 2026年第1期84-93,共10页
Grifola frondosa(Maitake)is traditionally valued for its health benefits,with polysaccharides being key bioactive components.This paper investigates a specific subfraction,Fraction D(GFP-D),evaluating its clinical eff... Grifola frondosa(Maitake)is traditionally valued for its health benefits,with polysaccharides being key bioactive components.This paper investigates a specific subfraction,Fraction D(GFP-D),evaluating its clinical effects and mechanisms in immune enhancement,adjunctive anti-tumor activity,and regulation of glucose/lipid metabolism.Three clinical trials were conducted.In an immune study,120 healthy volunteers(CD4+T cell count 500–1000 cells/μL)received 150 mg/day GFP-D for 8 weeks,resulting in significant increases in CD4+T cells(from 632±95 to 812±108 cells/μL,28.5%increase,within the physiological activation range),CD4+/CD8+ratio,NK cell activity,IL-2,and IFN-γ(all P<0.001 vs.placebo).An anti-tumor study with 80 advanced cancer patients(stratified by age,tumor stage,and histotype)showed that adding 1000 mg/day GFP-D to chemotherapy improved objective response rate(52.5%vs.30.0%,P=0.036,95%CI:1.02–3.87),one-year progression-free survival(55.8%vs.33.3%,P=0.022),and preserved immune parameters versus chemotherapy alone.A metabolic study in 90 type 2 diabetes patients found that 400 mg/day GFP-D for 12 weeks significantly lowered fasting glucose,HbA1c,total cholesterol,triglycerides,and LDL-C,while raising HDL-C(from 1.0±0.2 to 1.2±0.2 mmol/L,20%increase,supported by increased AMPK phosphorylation).Mechanistically,immune enhancement involves macrophage/dendritic cell activation via Dectin-1/TLR4 receptors(confirmed by increased receptor expression and downstream signaling molecules),promoting cytokine-driven T/NK cell responses.Anti-tumor effects stem from immunomodulation,direct induction of cancer cell apoptosis(via mitochondrial/caspase pathways,verified by increased Bax/Bcl-2 ratio and caspase-3 activation),and angiogenesis inhibition by downregulating VEGF.Metabolic benefits are linked to AMPK pathway activation in liver/muscle(confirmed by increased p-AMPK/AMPK ratio),enhancing glucose uptake and inhibiting gluconeogenesis/lipogenesis,alongside modulation of gut microbiota(increased Bifidobacterium and Lactobacillus abundance).All trials reported no severe adverse events related to GFP-D;liver/kidney function parameters(ALT,AST,creatinine,urea nitrogen)remained within normal ranges throughout the intervention.Collectively,GFP-D emerges as a multi-functional bioactive agent with substantial therapeutic potential. 展开更多
关键词 Grifola frondosa Maitake polysaccharide fraction D Immune modulation Adjunctive cancer therapy Glycemic control Lipid metabolism Clinical trial Mechanism of action
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A_(α)-Spectral Conditions for(a,b,k)-Factor-Critical Graphs and Fractional ID-[a,b]-Factor-Critical Covered Graphs
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作者 Yonglei CHEN Fei WEN 《Journal of Mathematical Research with Applications》 2026年第1期1-12,共12页
In this paper,we first give a sufficient condition for a graph being fractional ID-[a,b]-factor-critical covered in terms of its independence number and minimum degree,which partially answers the problem posed by Sizh... In this paper,we first give a sufficient condition for a graph being fractional ID-[a,b]-factor-critical covered in terms of its independence number and minimum degree,which partially answers the problem posed by Sizhong Zhou,Hongxia Liu and Yang Xu(2022).Then,an A_(α)-spectral condition is given to ensure that G is a fractional ID-[a,b]-factor-critical covered graph and an(a,b,k)-factor-critical graph,respectively.In fact,(a,b,k)-factor-critical graph is a graph which has an[a,b]-factor for k=0.Thus,these above results extend the results of Jia Wei and Shenggui Zhang(2023)and Ao Fan,Ruifang Liu and Guoyan Ao(2023)in some sense. 展开更多
关键词 A_(α)-spectral radius (a b k)-factor fractional(g f)-factor ID-factor-critical graph independence number
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Study on the Inhibitory Mechanism of Sophora japonica N-hexane Extract on Microcystis aeruginosa 被引量:4
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作者 周晓见 夏洁 +3 位作者 靳翠丽 缪莉 董昆明 封克 《Agricultural Science & Technology》 CAS 2011年第10期1543-1546,共4页
[Objective] The research aimed to analyze the inhibitory mechanism of Sophora japonica n-hexane extract which significantly inhibited Microcystis aeruginosa in the prior research.[Method] S.japonica n-hexane extract w... [Objective] The research aimed to analyze the inhibitory mechanism of Sophora japonica n-hexane extract which significantly inhibited Microcystis aeruginosa in the prior research.[Method] S.japonica n-hexane extract was used to treat M.aeruginosa.By inspecting chlorophyll a content,protein content,cell membrane permeability and superoxide dismutase(SOD) activity,the inhibitory mechanism of S.japonica n-hexane extract on M.aeruginosa was analyzed initially.[Result] S.japonica n-hexane extract destroyed the cell membrane system of M.aeruginosa,and increased the cell membrane permeability.The contents of chlorophyll a and protein respectively declined to 10% and 50% of that in the control group after cultivated for 7 d,which indicated the photosynthetic reaction system of M.aeruginosa was destroyed.In addition,under the effect of S.japonica n-hexane extract,SOD activity of M.aeruginosa increased in the early period and decreased in the latter period.[Conclusion] The possible inhibitory mechanism of S.japonica n-hexane extract on M.aeruginosa was destroying the cell membrane to increase the membrane permeability;destroying the photosynthetic reaction system to decrease the contents of photosynthetic pigment and protein;making SOD activity showing the phased variation. 展开更多
关键词 S.japonica M.aeruginosa n-hexane extract Inhibitory mechanism
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Effect of secondary pore distribution on adsorption diffusion performance of n-hexane on 5A zeolite pellets 被引量:1
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作者 杜旭东 刘宗健 +2 位作者 崔群 王海燕 姚虎卿 《Journal of Southeast University(English Edition)》 EI CAS 2011年第3期284-289,共6页
Adsorption rates of n-hexane on the 5A zeolite at 100 to 300 ℃ and 0.01 to 10 kPa are determined by an intelligent gravimetric analyzer (IGA-100), and the adsorption diffusion performance of n-hexane on 5A zeolite ... Adsorption rates of n-hexane on the 5A zeolite at 100 to 300 ℃ and 0.01 to 10 kPa are determined by an intelligent gravimetric analyzer (IGA-100), and the adsorption diffusion performance of n-hexane on 5A zeolite pellets with different secondary pore distributions is analyzed. The results indicate that 5A-1 and 5A-6 zeolites have similar micropore and mesopore size distribution, while the 5A-6 zeolite has a larger secondary pore volume when the pore diameter is between 0.1 and 1 μm and more secondary pores when the pore diameter is less than 0.01 μm. The effective diffusion coefficient of nhexane on the 5A-6 zeolite pellet is 10 ^-6 to 10 4 cm^2/s, about 2 to 5 times higher than that on the 5A-1 zeolite. The effective diffusion coefficient of n-hexane on the 5A-1 zeolite pellet improves from 5 × 10^-7 to 2 × 10 6cm^2/s when the temperature increases from 100 to 300 ~C. However, the effective diffusion coefficient of n-hexane on the 5A-6 zeolite remains almost unchanged at different temperatures. The molecular average free path of n-hexane decreases from 627.15-963.28 to 0.63-0, 96 Ixm with the adsorption pressure increasing from 0.01 to 10 kPa. Such a flee path is close to the secondary pore diameter, resulting in significant Knudsen diffusion in the secondary pores. Thus, the effective diffusion coefficient of n-hexane on the 5A zeolite pellets increases before 1 kPa and decreases after 1 kPa. 展开更多
关键词 5A zeolite pore structure secondary pore DIFFUSION n-hexane
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GC-MS Analysis of Essential oil and n-Hexane Extract from Moso Bamboo 被引量:2
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作者 刘志明 任海青 《Agricultural Science & Technology》 CAS 2012年第5期993-996,共4页
[Objective] This study aimed to analyze the chemical composition and yield of essential oil and n-hexane extract from moso bamboo to find active compounds with potential value. [Method] Essential oil and n-hexane extr... [Objective] This study aimed to analyze the chemical composition and yield of essential oil and n-hexane extract from moso bamboo to find active compounds with potential value. [Method] Essential oil and n-hexane extract were respectively extracted from moso bamboo of four different ages by using hydrodistillation and ultrasonic-assisted extraction with n-hexane, and analyzed with gas chromatography/mass spectrometry (GC/MS). [Result] The results show that cedrol (46.39%) is the first principal volatile component in essential oil of the middle stem of 7-year old moso bamboo; dibutyl phthalate (59.46%) is the first principal volatile component in n-hexane extract of the middle stem of 3-year old moso bamboo; yield of n-hexane extract is higher than that of essential oil from moso bamboo. [Conclusion] Cedrol is an active compound with potential value. 展开更多
关键词 Moso bamboo HYDRODISTILLATION Ultrasonic assistance n-hexane extract Gas chromatography/mass spectrometry (GC/MS)
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The Effect of n-Hexane on the Gonad Toxicity of Female Mice 被引量:4
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作者 LIU Jin HUANG Hui Ling +1 位作者 PANG Fen ZHANG Wen Chang 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2012年第2期189-196,共8页
Objective To investigate the toxic effects of n-hexane on the Ganod of female mice.Methods n-Hexane was administered to four groups of mice by inhalation at doses of 0,3.0,15.1,and 75.8 mL/m3 respectivelyfor five week... Objective To investigate the toxic effects of n-hexane on the Ganod of female mice.Methods n-Hexane was administered to four groups of mice by inhalation at doses of 0,3.0,15.1,and 75.8 mL/m3 respectivelyfor five weeks.Each group consisted of 10 mice,of which half were injected in first with 10 IU of pregnant mare serum gonadotrophin(PMSG) on the 33rd days,and then with 10 IU of human chorionic gonadotrophin(HCG) 48 hrs later.After the treatment,mouse sera were sampled and ovulating hormone(LH),follicle-stimulating hormone(FSH),estradiol(E2),and progesterone(P4) levels were measured by electrochemiluminescence immunoassays(ECLIA).In each group,the right ovaries of the non-super-ovulated mice were stained with hematoxylin and eosin while ovaries on the left side were prepared with the TUNEL method in order to detect apoptotic cells.Results The duration of the diestrus stage decreased significantly(P0.05) in the 75.8 mL/m3 group.All super-ovulated mice in each treatment group produced fewer eggs than those in the control group(P0.05).The number of follicles in ovaries in the 75.8 mL/m3 group was smaller compared with the control group(P0.05).The serum P4 levels in each treatment group were lower than those in the control group(F=6.196,P0.01).The cell apoptotic rate in the 75.8 mL/m3 group was higher(P0.05).Conclusion n-Hexane may have directly mediated via alterations hormone secretion and promoted granulosal cell apoptotic,which may be one of the important mechanisms for n-hexane induced mouse ovary impairment. 展开更多
关键词 n-hexane SUPEROVULATION HORMONE OVARY Cell apoptotic rate
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Pt supported on Zn modified silicalite-1 zeolite as a catalyst for n-hexane aromatization 被引量:4
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作者 Guodong Liu Jiaxu Liu +3 位作者 Ning He Shishan Sheng Guiru Wang Hongchen Guo 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2019年第7期96-103,共8页
Platinum(Pt)supported on Zinc(Zn)modified silicalite-1(S-1)zeolite(denoted as Pt-Zn/S-1)was prepared by using a wetness-impregnation method and applied in the n-hexane aromatization reaction for the first time.Both Le... Platinum(Pt)supported on Zinc(Zn)modified silicalite-1(S-1)zeolite(denoted as Pt-Zn/S-1)was prepared by using a wetness-impregnation method and applied in the n-hexane aromatization reaction for the first time.Both Lewis and Bronsted acid sites were detected in Pt-Zn/S-1 catalyst by means of FT-IR adsorption of NH3 experiment,which were identified as mostly weak and medium ones.Besides,Pt and Zn species showed strong interaction,as revealed by the TPR(Temperature-programmed reduction)and XPS(X-ray photoelectron spectroscopy)experiments.Pt-Zn/S-1 catalyst exhibited excellent aromatization function rather than isomerization and cracking side reactions in the conversion of n-hexane.Pulse experimental study showed that 75.6%of n-hexane conversion and 76.8%of benzene selectivity were obtained over Pt0.1-Zn60/S-l catalyst at 550℃ and under atmospheric pressure.By spectroscopy tests and pulse experimental results,it was concluded that the n-hexane aromatization over Pt-Zn/S-1 catalyst follows a metal-acid bifunctional mechanism.Furthermore,with the assistance of Zn,the electron-deficient Pt species in Pt-Zn/S-1 showed good sulfur tolerance performance. 展开更多
关键词 SILICALITE-1 ZEOLITE Pt-Zn/Silicalite-1 n-hexane AROMATIZATION Sulfur-resistance
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Photolysis of mono- through deca-chlorinated biphenyls by ultraviolet irradiation in n-hexane and quantitative structure-property relationship analysis 被引量:3
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作者 LI Xue FANG Lei HUANG Jun YU Gang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第6期753-759,共7页
The photolysis of 16 polychlorinated biphenyls (PCBs) (including mono- through deca-chlorinated) in n-hexane was investigated under ultraviolet irradiation using a 500-W high-pressure mercury lamp. Photolysis of P... The photolysis of 16 polychlorinated biphenyls (PCBs) (including mono- through deca-chlorinated) in n-hexane was investigated under ultraviolet irradiation using a 500-W high-pressure mercury lamp. Photolysis of PCBs follows pseudo-first-order reaction kinetics, with photolysis rate constants ranging between 0.0011 s^-1 for PCB-52 and 0.0574 s^-1 for PCB-118. The degradation rates of PCBs by high-pressure mercury lamp irradiation were remarkably independent with respect to the degree of chlorination. Furthermore, partial least squares (PLS) models were developed to provide insight into which aspect of the molecular structure influenced PCB photolysis rate constants. It was found that the photolysis rates of PCBs increased with an increase in the net charge on the carbon atom (qc), (ELUMO-EHOMO)^2, and the Y-axis dipole moment (μy) values, or the decrease in the energy of the second highest occupied molecular orbital (EHOMO-1), energy of the lowest unoccupied molecular orbital (ELUMO), ELUMO + EHOMO, ELUMO - EHOMO, most positive atomic charge (q^+), and the twist angle of the chlorine atom (TA) values. 展开更多
关键词 PHOTOLYSIS polychlorinated biphenyls n-hexane partial least squares quantum chemical descriptors
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The impact of n-hexane on the secretion of mouse estrogen and progesterone 被引量:3
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作者 Huiling Huang Jin Liu +1 位作者 Fen Pang Wenchang Zhang 《Advances in Bioscience and Biotechnology》 2011年第6期429-433,共5页
Aim: To study the toxic effect of n-hexane on sex hormone levels, including its effect on ovarian sex hormone secretion levels and the underlying mechanism. 1) In vivo experiment: The mice were exposed to n- hexane by... Aim: To study the toxic effect of n-hexane on sex hormone levels, including its effect on ovarian sex hormone secretion levels and the underlying mechanism. 1) In vivo experiment: The mice were exposed to n- hexane by static inhalation of doses of 0, 3.0, 15.1 or 75.8 ml/m3 once a day (4 hours), 7 days a week, for 5 consecutive weeks. After exposure, mouse sera were sampled to measure estradiol (E2) and progesterone (P4) levels by electrochemiluminescence immunoassays (ECLIA). 2) In vitro experiment: mice at different stages of the estrous cycle were sacrificed and their minced tissue pieces were incubated in medium containing hexane-2,5-dione (2,5-HD). Then, the E2 and P4 levels in the media were measured by ECLIA. In vivo assays, the serum P4 levels in each group were lower than the control group, which was statistically significant (F = 6.196, P 2 level of 75.8 mL/m3 dosage group was decreased (96.9522 ± 7.8652)) compared to the control group (119.1600 ± 25.6420), with statistical significance (P 4 levels of 15.1 mL/m3 and 75.8 mL/m3 dosage groups were also decreased (18.5938 ± 12.485pmol/L, 13.5550 ± 5.7789 pmol/L) and were statistically significantly (F = 6.196, P In vitro, the E2 levels at various stages of the estrous cycle were significantly different from the control groups (P In vitro, different concentrations of 2, 5-HD significantly inhibited the P4 level (P 4 levels at various stages of the estrous cycle were also significantly different from controls (P 0.05). The results indicate that n-hexane may inhibit release of ovarian E2 and P4, which may be the main reason for the interference of the reproductive endocrine system by n-hexane. 展开更多
关键词 n-hexane SEX HORMONE Interference of REPRODUCTIVE ENDOCRINE System
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N-hexane Alters the Maturation of Oocytes and Induces Apoptosis in Mice 被引量:1
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作者 LIU Jin HUANG Lei +4 位作者 SUN Yan LI Yu Chen ZHU Jian Lin WANG Wen Xiang ZHANG Wen Chang 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2013年第9期735-741,共7页
Objective This study was aimed to determine the effects of n-hexane on the maturation of mouse oocytes. Methods Cell culture was used to observe the maturation of mouse oocytes and CLSM was employed to determine their... Objective This study was aimed to determine the effects of n-hexane on the maturation of mouse oocytes. Methods Cell culture was used to observe the maturation of mouse oocytes and CLSM was employed to determine their apoptosis. Results Germinal vesicle breakdown (GVBD) and extrusion of the first polar body in mouse oocytes were significantly inhibited by n-hexane. After fertilization, the number of eggs in the mouse was significantly reduced by n-hexane. Mitochondrial membrane potentials (A^Um) were altered in mouse oocytes that were leading to apoptosis of the oocytes. Conclusion N-hexane might have affected the maturation of oocytes, causing alteration of ~qJm and leading to apoptosis which maybe one of the most imn(~rt^nt rnpch^ni^nn~ 展开更多
关键词 n-hexane MATURATION FERTILIZATION Mitochondrial membrane potential
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Influence of Wind Deviation Angle on n-Hexane Evaporation Loss of Internal Floating-Roof Tanks 被引量:1
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作者 Huang Weiqiu Xu Manlin +2 位作者 Li Fei Ji Hong Fang Jie 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2020年第2期46-55,共10页
With the increasing attention to environmental protection,it is still necessary to strictly control the oil evaporation loss from the IFRT(internal floating-roof tank)to the atmosphere.Upon using n-hexane as a represe... With the increasing attention to environmental protection,it is still necessary to strictly control the oil evaporation loss from the IFRT(internal floating-roof tank)to the atmosphere.Upon using n-hexane as a representative of light oil,the effects of the WDAs(wind deviation angles)on airflow distribution,the wind speed,the n-hexane vapor concentration,and the evaporation loss rate in the IFRT were investigated,and the mass transfer of the vapor-air was analyzed.The results are shown as follows:when the WDA is 0°,the vapor concentration in the gas space above the floating deck is the lowest;when the WDA is 22.5°,the oil evaporation loss rate is the largest;when the WDA is 45°,the vapor concentration is the highest,but the evaporation loss rate is the smallest.It is recommended to arrange the vent to the wind direction with an angle of 45°to reduce the evaporation loss and protect the atmospheric environment. 展开更多
关键词 wind deviation angle n-hexane evaporation loss internal floating-roof tank numerical simulation wind-tunnel experiment
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Bimetallic CoNi single atoms supported on three-dimensionally ordered mesoporous chromia:highly active catalysts for n-hexane combustion 被引量:1
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作者 Xiuqing Hao Yuxi Liu +4 位作者 Jiguang Deng Lin Jing Jia Wang Wenbo Pei Hongxing Dai 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第7期1122-1137,共16页
Developing the alternative supported noble metal catalysts with low cost,high catalytic efficiency,and good resistance toward carbon dioxide and water vapor is critically demanded for the oxidative removal of volatile... Developing the alternative supported noble metal catalysts with low cost,high catalytic efficiency,and good resistance toward carbon dioxide and water vapor is critically demanded for the oxidative removal of volatile organic compounds(VOCs).In this work,we prepared the mesoporous chromia-supported bimetallic Co and Ni single-atom(Co_(1)Ni_(1)/meso-Cr_(2)O_(3))and bimetallic Co and Ni nanoparticle(Co_(NP)Ni_(NP)/mesoCr_(2)O_(3))catalysts adopting the one-pot polyvinyl pyrrolidone(PVP)-and polyvinyl alcohol(PVA)-protecting approaches,respectively.The results indicate that the Co_(1)Ni_(1)/meso-Cr_(2)O_(3)catalyst exhibited the best catalytic activity for n-hexane(C_(6)H_(14))combustion(T_(50%)and T_(90%)were 239 and 263℃ at a space velocity of 40,000 mL g^(-1)h^(-1);apparent activation energy and specific reaction rate at 260℃ were 54.7 kJ mol^(-1)and 4.3×10^(-7)mol g^(-1)_(cat)s^(-1),respectively),which was associated with its higher(Cr^(5+)+Cr^(6+))amount,large n-hexane adsorption capacity,and good lattice oxygen mobility that could enhance the deep oxidation of n-hexane,in which Ni_(1) was beneficial for the enhancements in surface lattice oxygen mobility and low-temperature reducibility,while Co_(1) preferred to generate higher contents of the high-valence states of chromium and surface oxygen species as well as adsorption and activation of n-hexane.n-Hexane combustion takes place via the Mars van Krevelen(MvK)mechanism,and its reaction pathways are as follows:n-hexane→olefins or 3-hexyl hydroperoxide→3-hexanone,2-hexanone or 2,5-dimethyltetrahydrofuran→2-methyloxirane or 2-ethyl-oxetane→acrylic acid→CO_x→CO_(2)and H_(2)O. 展开更多
关键词 Three-dimensional ordered mesoporous chromium oxide Supported bimetallic single-atom catalyst Cobalt-nickel single atoms n-hexane combustion Catalytic reaction mechanism
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Heterogeneity of Adsorption Sites and Adsorption Kinetics of n-Hexane on Metal–Organic Framework MIL-101(Cr) 被引量:1
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作者 孙雪娇 苗晋朋 +2 位作者 肖静 夏启斌 赵祯霞 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第9期962-967,共6页
The heterogeneity of adsorption sites and adsorption kinetics of n-hexane on a chromium terephthalate-based metal-organic framework MIL-10^1 (Cr) were studied by gravimetric method and temperature-programmed desorpt... The heterogeneity of adsorption sites and adsorption kinetics of n-hexane on a chromium terephthalate-based metal-organic framework MIL-10^1 (Cr) were studied by gravimetric method and temperature-programmed desorption (TPD) experiments. The MIL-101 crystals were synthesized by microwave irradiation method. The ad- sorption isotherms and kinetic curves of n-hexane on the MIL-101 were measured. Desorption activation energies of n-hexane from the MIL-10^1 were estimated by TPD experiments. The resulthowed that equilibrium amount ofn-hexane adsorbed on the MIL-10^1 was up to 5.62 mmol.g- 1 at 298 K and 1.6 x10^4 Pa, much higher than that of some activated carbons, zeolltes and so on. The isotherms of n-hexane on the MIL-101 could be well fitted with Langmuir-Freundlich model. TPD spectra exhibit two types of adsorption sites on the MIL-101 with desorption activation energies of 39.41 and 86.69 kJ. mol-1. It reflects the surface energy heterogeneity on the MIL-10I frameworks for n-hexane adsorption. The diffusion coefficients of n-hexane are in the range of (1.35- 2.35 ) x 10 - 1 o cm2. s - 1 with ad sorotion activation enerv of 16.33 kl. mol - 1. 展开更多
关键词 Adsorption Kinetics n-hexane MIL-101 Heterogeneity
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N-Hexane Isomerization on Ni-Pt/Catalysts Supported on Mordenite 被引量:3
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作者 Geovana S.V.Martins Everton R.F.dos Santos +3 位作者 Meiry G.F.Rodrigues Gina Pecchi Carlos M.N.Yoshioka Dilson Cardoso 《Modern Research in Catalysis》 2013年第4期119-126,共8页
The aim of this work was to evaluate the catalytic properties for n-hexane isomerization of bifunctional monometallic (Ni or Pt) and bimetallic catalysts (Pt-Ni), using HMOR zeolite as support. The method used for met... The aim of this work was to evaluate the catalytic properties for n-hexane isomerization of bifunctional monometallic (Ni or Pt) and bimetallic catalysts (Pt-Ni), using HMOR zeolite as support. The method used for metal dispersion in the zeolite was competitive ion exchange using ammine complexes [Ni(NH3)6]Cl2 and [Pt(NH3)4]Cl2 as precursors. The catalysts were characterized by X-Ray diffraction, X-Ray energy dispersion spectroscopy, temperature-programmed reduction and transmission electron microscopy. The n-hexane isomerization reaction using the catalysts was carried out to evaluate the catalyst activity. The reaction was carried out in a fixed bed reactor operating at 250?C, 1 atm, H2/C6 = 9 molar ratio. The profiles obtained from TPR suggest that, for bimetallic catalysts, the presence of platinum facilitates the reduction of Ni2+ cations. The bimetallic catalysts presented a higher activity in the isomerization of n-hexane when compared to the monometallic ones, as well better stability as the Pt content in the solid increases. 展开更多
关键词 n-hexane ISOMERIZATION MORDENITE Nickel PLATINUM
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