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Endocrine-Disrupting Chemicals: Possible Genesis of Ovarian Tumors
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作者 Kasonde Chanda Ziwei Wang +2 位作者 Shen Ning Xue Bin Yingxiao Yan 《Open Journal of Obstetrics and Gynecology》 2023年第6期1025-1037,共13页
Background: Prolonged exposure to environmental toxicants like endocrine-disrupting chemicals has been linked to several ovarian pathologies. Exposure to endocrine-disrupting chemicals may start at any time of life fr... Background: Prolonged exposure to environmental toxicants like endocrine-disrupting chemicals has been linked to several ovarian pathologies. Exposure to endocrine-disrupting chemicals may start at any time of life from the fetal stage to adulthood resulting in various health complications The purpose of our study is to compare the concentration levels and association of benzopyrene, bisphenol A and genistein in patients with ovarian tumors and normal control group. We also sort to evaluate the predictive performance of benzopyrene, bisphenol A and genistein in patients with ovarian tumors. Methods: A case-control study was conducted for randomly selected participants involving 30 patients and 30 controls. 30 patients with radiologically diagnosed and histopathological confirmed ovarian tumors were included in the study between January 2022 and December 2022. Urine samples from each group were analyzed using liquid chromatography-mass spectrometry. Descriptive analysis for normally distributed continuous variables was done accordingly. Concentration levels of endocrine-disrupting chemicals were assessed using the Mann-Whitney test. The association of endocrine-disrupting chemicals with pathological ovarian tumors was analyzed using binary logistic regression. Evaluation of the diagnostic performance of endocrine-disrupting chemicals was analyzed using the ROC curve. Results: Overall, patients were significantly (P = 0.000) older than the healthy controls. Mean years (SD) were 36.7 (7.90) and 28.8 years (4.89) for patients and normal women respectively. Endometriomas had the highest incidence of 50%. The level of benzopyrene and bisphenol A in patients was significantly higher than those in the control group, while the level of genistein was significantly higher in normal controls. Benzopyrene and bisphenol A were significantly associated with ovarian cysts, and the incidence of pathological ovarian cysts was positively correlated to these EDCs, with OR value 64.79 (P = 0.005) for benzopyrene and 9.609 (P = 0.001) for bisphenol A. Genistein was significantly negatively correlated with the incidence of pathological ovarian tumors, with OR value of 0.153 (P = 0.007). Diagnostic performance on the AUC for benzopyrene, bisphenol A and genistein&l. 展开更多
关键词 Environmental Toxicants endocrine-disrupting chemical Ovarian Cyst Ovarian Tumor
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Apoptosis-inducing activity of endocrine-disrupting chemicals in cultured PC12 cells
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作者 Harue Sasaya Kazuya Yasuzumi +5 位作者 Hiroki Maruoka Ayumi Fujita Yuichi Kato Taiki Waki Koji Shimoke Toshihiko Ikeuchi 《Advances in Biological Chemistry》 2012年第2期92-105,共14页
Endocrine-disrupting chemicals (EDCs) are known to exert estrogen-like effects that are similar to those made by naturally produced hormones or by inhibition of the receptors in the cell receiving the hormones. Recent... Endocrine-disrupting chemicals (EDCs) are known to exert estrogen-like effects that are similar to those made by naturally produced hormones or by inhibition of the receptors in the cell receiving the hormones. Recently, several reports have indicated that EDCs can affect the developing central nervous system. In our current study, we report that some EDCs induce apoptosis in cultured PC12 cells and can be classified into three groups. Bisphenol A (BPA), p-nonylphenol (NP) and tributyltin chloride (TBT) were found to induce endoplasmic reticulum (ER) stress-associated apoptosis and activate the unfolded protein response (UPR) system, whereas benomyl (beno) induced non-ER stress-associated apoptosis. The half-maximal apoptosis-inducing concentrations (IC50) of these EDCs were 160 μM for BPA, 25.6 μM for NP, 640 nM for TBT and 48 μM for beno. Although these concentrations are higher than those found in the environment, some EDCs may have apoptotic effects on various cells in the body, including neurons, through their accumulation in the body over time or condensation through the food chain. On the other hand, benzopyrene, fenvalerate, styrene monomer and bis(2-ethylhexyl)phthalate did not induce apoptosis in PC12 cells. We analyzed also whether apoptosis-inducing EDCs had an estrogen-like effect on cultured PC12 cells transfected with a luciferase reporter plasmid, the activity of which is dependent on estrogen receptor α. We found that BPA had an estrogen-like effect (EC50 = 5.9 μM) but that NP, TBT and beno did not in transfected PC12 cells. These results suggest that BPA may predomi-nantly exert estrogenic effects, but others may pre-dominantly have apoptosis-inducing effects on cells in the body exposed to a polluted environment. 展开更多
关键词 endocrine-disrupting chemicalS ER Stress Apoptosis ESTROGEN RECEPTOR PC12 Cells
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The silent threat and countermeasures:Navigating the mixture risk of endocrine-disrupting chemicals on pregnancy loss in China
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作者 Yaqian Xu Thanh Wang +2 位作者 Jia Yin Ligang Hu Chunyang Liao 《Eco-Environment & Health》 2024年第3期266-270,共5页
Currently,many countries and regions worldwide face the challenge of declining population growth due to persistently low rates of female reproduction.Since 2017,China's birth rate has hit historic lows and continu... Currently,many countries and regions worldwide face the challenge of declining population growth due to persistently low rates of female reproduction.Since 2017,China's birth rate has hit historic lows and continued to decline,with the death rate now equaling the birth rate.Concerns have emerged regarding the potential impact of environmental contaminants on reproductive health,including pregnancy loss.Endocrine-disrupting chemicals(EDCs)like phthalate esters(PAEs),bisphenol A(BPA),triclosan(TCS),and perfluoroalkyl substances(PFASs)have raised attention due to their adverse effects on biological systems.While China's 14th Five-Year Plan(2021–2025)for national economic and social development included the treatment of emerging pollutants,including EDCs,there are currently no national appraisal standards or regulatory frameworks for EDCs and their mixtures.Addressing the risk of EDC mixtures is an urgent matter that needs consideration from China's perspective in the near future.In this Perspective,we delve into the link between EDC mixture exposure and pregnancy loss in China.Our focus areas include establishing a comprehensive national plan targeting reproductive-aged women across diverse urban and rural areas,understanding common EDC combinations in women and their surrounding environment,exploring the relationship between EDCs and pregnancy loss via epidemiology,and reconsidering the safety of EDCs,particularly in mixtures and low-dose scenarios.We envision that this study could aid in creating preventive strategies and interventions to alleviate potential risks induced by EDC exposure during pregnancy in China. 展开更多
关键词 endocrine-disrupting chemicals Targeted and nontargeted analysis Mixture effect Birth rate Pregnancy loss
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Jet formation and penetration performance of a double-layer charge liner with chemically-deposited tungsten as the inner liner 被引量:2
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作者 Bihui Hong Wenbin Li +2 位作者 Yiming Li Zhiwei Guo Binyou Yan 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期374-385,共12页
This paper proposes a type of double-layer charge liner fabricated using chemical vapor deposition(CVD)that has tungsten as its inner liner.The feasibility of this design was evaluated through penetration tests.Double... This paper proposes a type of double-layer charge liner fabricated using chemical vapor deposition(CVD)that has tungsten as its inner liner.The feasibility of this design was evaluated through penetration tests.Double-layer charge liners were fabricated by using CVD to deposit tungsten layers on the inner surfaces of pure T2 copper liners.The microstructures of the tungsten layers were analyzed using a scanning electron microscope(SEM).The feasibility analysis was carried out by pulsed X-rays,slug-retrieval test and static penetration tests.The shaped charge jet forming and penetration law of inner tungsten-coated double-layer liner were studied by numerical simulation method.The results showed that the double-layer liners could form well-shaped jets.The errors between the X-ray test results and the numerical results were within 11.07%.A slug-retrieval test was found that the retrieved slug was similar to a numerically simulated slug.Compared with the traditional pure copper shaped charge jet,the penetration depth of the double-layer shaped charge liner increased by 11.4% and>10.8% respectively.In summary,the test results are good,and the numerical simulation is in good agreement with the test,which verified the feasibility of using the CVD method to fabricate double-layer charge liners with a high-density and high-strength refractory metal as the inner liner. 展开更多
关键词 Shaped charge chemical vapor deposition TUNGSTEN Double-layer charge liner X-ray PENETRATION
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Valorization of Camellia oleifera oil processing byproducts to value-added chemicals and biobased materials: A critical review 被引量:1
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作者 Xudong Liu Yiying Wu +11 位作者 Yang Gao Zhicheng Jiang Zicheng Zhao Wenquan Zeng Mingyu Xie Sisi Liu Rukuan Liu Yan Chao Suli Nie Aihua Zhang Changzhu Li Zhihong Xiao 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第1期28-53,共26页
The C.oleifera oil processing industry generates large amounts of solid wastes,including C.oleifera shell(COS)and C.oleifera cake(COC).Distinct from generally acknowledged lignocellulosic biomass(corn stover,bamboo,bi... The C.oleifera oil processing industry generates large amounts of solid wastes,including C.oleifera shell(COS)and C.oleifera cake(COC).Distinct from generally acknowledged lignocellulosic biomass(corn stover,bamboo,birch,etc.),Camellia wastes contain diverse bioactive substances in addition to the abundant lignocellulosic components,and thus,the biorefinery utilization of C.oleifera processing byproducts involves complicated processing technologies.This reviewfirst summarizes various technologies for extracting and converting the main components in C.oleifera oil processing byproducts into value-added chemicals and biobased materials,as well as their potential applications.Microwave,ultrasound,and Soxhlet extractions are compared for the extraction of functional bioactive components(tannin,flavonoid,saponin,etc.),while solvothermal conversion and pyrolysis are discussed for the conversion of lignocellulosic components into value-added chemicals.The application areas of these chemicals according to their properties are introduced in detail,including utilizing antioxidant and anti-in-flammatory properties of the bioactive substances for the specific application,as well as drop-in chemicals for the substitution of unrenewable fossil fuel-derived products.In addition to chemical production,biochar fabricated from COS and its applications in thefields of adsorption,supercapacitor,soil remediation and wood composites are comprehensively reviewed and discussed.Finally,based on the compositions and structural characteristics of C.oleifera byproducts,the development of full-component valorization strategies and the expansion of the appli-cationfields are proposed. 展开更多
关键词 Camellia oleifera shell Camellia oleifera cake Value-added chemicals Bioactive components Biobased materials
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A novel method for simulating nuclear explosion with chemical explosion to form an approximate plane wave: Field test and numerical simulation 被引量:1
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作者 Wei Ming Xiaojie Yang +3 位作者 Yadong Mao Xiang Wang Manchao He Zhigang Tao 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期2137-2153,共17页
A nuclear explosion in the rock mass medium can produce strong shock waves,seismic shocks,and other destructive effects,which can cause extreme damage to the underground protection infrastructures.With the increase in... A nuclear explosion in the rock mass medium can produce strong shock waves,seismic shocks,and other destructive effects,which can cause extreme damage to the underground protection infrastructures.With the increase in nuclear explosion power,underground protection engineering enabled by explosion-proof impact theory and technology ushered in a new challenge.This paper proposes to simulate nuclear explosion tests with on-site chemical explosion tests in the form of multi-hole explosions.First,the mechanism of using multi-hole simultaneous blasting to simulate a nuclear explosion to generate approximate plane waves was analyzed.The plane pressure curve at the vault of the underground protective tunnel under the action of the multi-hole simultaneous blasting was then obtained using the impact test in the rock mass at the site.According to the peak pressure at the vault plane,it was divided into three regions:the stress superposition region,the superposition region after surface reflection,and the approximate plane stress wave zone.A numerical simulation approach was developed using PFC and FLAC to study the peak particle velocity in the surrounding rock of the underground protective cave under the action of multi-hole blasting.The time-history curves of pressure and peak pressure partition obtained by the on-site multi-hole simultaneous blasting test and numerical simulation were compared and analyzed,to verify the correctness and rationality of the formation of an approximate plane wave in the simulated nuclear explosion.This comparison and analysis also provided a theoretical foundation and some research ideas for the ensuing study on the impact of a nuclear explosion. 展开更多
关键词 Approximate plane wave Multi-hole simultaneous blasting chemical explosion Nuclear explosion Pressure sensor inclusion
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Integrated Effects of Phosphate Rock and Chemical Fertilizers on the Dynamics of Soil Bacterial in Acidic Rice Paddy Soils of Man (Ivory Coast)
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作者 Affi Jeanne Bongoua-Devisme Sainte Adélaïde Ahya Edith Kouakou +1 位作者 Konan-Kan Hippolyte Kouadio Franck Michaël Lemonou Bahan 《Advances in Microbiology》 CAS 2024年第10期513-531,共19页
In agricultural soils, phosphorus is often limited, leading farmers to employ artificial supplementation through both inorganic and organic fertilization methods due to its restricted availability. Soil fertilization ... In agricultural soils, phosphorus is often limited, leading farmers to employ artificial supplementation through both inorganic and organic fertilization methods due to its restricted availability. Soil fertilization has the potential to augment both the abundance and diversity of bacterial communities. Our study aimed to assess the effects of phosphate amendments, derived from natural phosphate rock, and chemical fertilizers (TSP, NPK), on the density and diversity of bacterial communities within the study plots. We developed and applied eight phosphate amendments during the initial cultivation cycle. Soil samples were collected post 1st and 2nd cultivation cycles, and the quantification of both total and cultivable phosphate-solubilizing bacteria (PSB) was conducted. Additionally, we analyzed bacterial community structure, α-diversity (Shannon Diversity Index, Evenness Index, Chao1 Index). The combination of natural phosphate rock (PR) and chemical fertilizers (TSP, NPK) significantly increased (p 7 bacteria/g dry soil) and phosphate-solubilizing bacteria (0.01 to 6.8 × 107 PSB/g dry soil) in comparison to unamended control soils. The diversity of bacterial phyla (Firmicutes, Actinobacteria, Proteobacteria, Halobacterota, Chloroflexia) observed under each treatment remained consistent regardless of the nature of the phosphate amendment applied. However, changes in the abundance of the bacterial phyla populations were observed as a function of the nature of the phosphate amendment or chemical fertilizer. It appears that the addition of excessive natural phosphate rock does not alter the number and the diversity of soil microorganisms population despite successive cultivation cycles. However, the addition of excessive chemical fertilizer reduces soil microorganisms density and structure after the 2nd cultivation cycle. 展开更多
关键词 Phosphate Amendments Phosphate Solubilizing Bacteria P-Cycle Genes chemical Fertilizer
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Experimental investigation into effects of the natural polymer and nanoclay particles on the EOR performance of chemical flooding in carbonate reservoirs
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作者 Amir Mohammad Zamani Ashkan Moslemi Kamran Hassani 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期951-961,共11页
This paper aims to investigate the tragacanth gum potential as a natural polymer combined with natural clay mineral(montmorillonite,kaolinite,and illite)nanoparticles(NPs)to form NP-polymer suspension for enhanced oil... This paper aims to investigate the tragacanth gum potential as a natural polymer combined with natural clay mineral(montmorillonite,kaolinite,and illite)nanoparticles(NPs)to form NP-polymer suspension for enhanced oil recovery(EOR)in carbonate reservoirs.Thermal gravimetric analysis(TGA)tests were conducted initially in order to evaluate the properties of tragacanth gum.Subsequently,scanning electron microscopy(SEM)and energy-dispersive X-ray(EDX)tests were used to detect the structure of clay particles.In various scenarios,the effects of natural NPs and polymer on the wettability alteration,interfacial tension(IFT)reduction,viscosity improvement,and oil recovery were investigated through contact angle system,ring method,Anton Paar viscometer,and core flooding tests,respectively.The entire experiment was conducted at 25,50,and 75℃,respectively.According to the experimental results,the clay minerals alone did not have a significant effect on viscosity,but the addition of minerals to the polymer solution leads to the viscosity enhancement remarkably,resulting mobility ratio improvement.Among clay NPs,the combination of natural polymer and kaolinite results in increased viscosity at all temperatures.Considerable wettability alteration was also observed in the case of natural polymer and illite NPs.Illite in combination with natural polymer showed an ability in reducing IFT.Finally,the results of displacement experiments revealed that the combination of natural polymer and kaolinite could be the best option for EOR due to its substantial ability to improve the recovery factor. 展开更多
关键词 chemical flooding Tragacanth gum Clay nanoparticle WETTABILITY IFT
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Rational design of F,N-rich artificial interphase via chemical prelithiation initiation strategy enabling high coulombic efficiency and stable micro-sized SiO anodes
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作者 Quanyan Man Hengtao Shen +3 位作者 Chuanliang Wei Baojuan Xi Shenglin Xiong Jinkui Feng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期224-232,共9页
Silicon monoxide(SiO)is regarded as a potential candidate for anode materials of lithium-ion batteries(LIBs).Unfortunately,the application of SiO is limited by poor initial Coulombic efficiency(ICE)and unsteady solid ... Silicon monoxide(SiO)is regarded as a potential candidate for anode materials of lithium-ion batteries(LIBs).Unfortunately,the application of SiO is limited by poor initial Coulombic efficiency(ICE)and unsteady solid electrolyte interface(SEI),which induce low energy,short cycling life,and poor rate properties.To address these drawbacks of SiO,we achieve in-situ construction of robust and fast-ion conducting F,N-rich SEI layer on prelithiated micro-sized SiO(P-μSiO)via the simple and continuous treatment ofμSiO in mild lithium 4,4′-dimethylbiphenyl solution and nonflammable hexafluorocyclotriphosphazene solution.Chemical prelithiation eliminates irreversible capacity through pre-forming inactive lithium silicates.Meanwhile,the symbiotic F,N-rich SEI with good mechanical stability and fast Li^(+)permeability is conductive to relieve volume expansion ofμSiO and boost the Li+diffusion kinetics.Consequently,the P-μSiO realizes an impressive electrochemical performance with an elevated ICE of 99.57%and a capacity retention of 90.67%after 350 cycles.Additionally,the full cell with P-μSiO anode and commercial LiFePO_(4) cathode displays an ICE of 92.03%and a high reversible capacity of 144.97 mA h g^(-1).This work offers a general construction strategy of robust and ionically conductive SEI for advanced LIBs. 展开更多
关键词 chemical prelithiation Silicon monoxide SEI Lithium-ion batteries INTERPHASE engineering
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Mn-doped SrCoO_(3-δ) Perovskite Oxides for Ethylene Production via Chemical Looping Oxidative Dehydrogenation of Ethane
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作者 Li Zhi Liu Linjiao +4 位作者 Hao Daijun Ren Xiaohang Shen Fangxia Li Xin Yu Anping 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2024年第3期53-62,共10页
Chemical looping oxidative dehydrogenation (CL-ODH) is an economically promising method for convertingethane into higher value-added ethylene utilizing lattice oxygen in redox catalysts, also known as oxygen carriers.... Chemical looping oxidative dehydrogenation (CL-ODH) is an economically promising method for convertingethane into higher value-added ethylene utilizing lattice oxygen in redox catalysts, also known as oxygen carriers. Inthis study, perovskite-type oxide SrCoO_(3-δ) and B-site Mn ion-doped oxygen carriers (SrCo_(1-x)MnxO_(3-δ), x=0.1, 0.2, 0.3)were prepared and tested for the CL-ODH of ethane. The oxygen-deficient perovskite SrCoO_(3-δ) exhibited high ethyleneselectivity of up to 96.7% due to its unique oxygen vacancies and lattice oxygen migration rates. However, its low ethyleneyield limits its application in the CL-ODH of ethane. Mn doping promoted the reducibility of SrCoO_(3-δ) oxygen carriers,thereby improving ethane conversion and ethylene yield, as demonstrated by characterization and evaluation experiments.X-ray diffraction results confirmed the doping of Mn into the lattice of SrCoO_(3-δ), while X-ray photoelectron spectroscopy(XPS) indicated an increase in lattice oxygen ratio upon incorporation of Mn into the SrCoO_(3-δ) lattice. Additionally, H2temperature-programmed reduction (H2-TPR) tests revealed more peaks at lower temperature reduction zones and a declinein peak positions at higher temperatures. Among the four tested oxygen carriers, SrCo0.8Mn0.2O_(3-δ) exhibited satisfactoryperformance with an ethylene yield of 50% at 710 °C and good stability over 20 redox cycles. The synergistic effect of Mnplays a key role in increasing ethylene yields of SrCoO_(3-δ) oxygen carriers. Accordingly, SrCo0.8Mn0.2O_(3-δ) shows promisingpotential for the efficient production of ethylene from ethane via CL-ODH. 展开更多
关键词 ETHANE ETHYLENE PEROVSKITE chemical looping oxidative dehydrogenation
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Geochemical characteristics and environmental implications of loess sequences in the Loess Plateau
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作者 ZHANG Jialin ZHAO Zhongqiang +5 位作者 XIA Dinghong LI Zhenyang ZENG Liyuan HE Hongming SONG Yinxian CHEN Zhong 《High Technology Letters》 EI CAS 2024年第3期310-321,共12页
The major,trace,and rare earth elements of the Duanjiapo(DJP)section in the south of the Loess Plateau,the Jiaxian(JX)section in the north,and the Jiuzhoutai(JZT)section in the west are studied.The results show that t... The major,trace,and rare earth elements of the Duanjiapo(DJP)section in the south of the Loess Plateau,the Jiaxian(JX)section in the north,and the Jiuzhoutai(JZT)section in the west are studied.The results show that the main elemental characteristics of loess in three profiles are consistent with the upper continental crust(UCC).In terms of trace elements,Th,Nb,Zr,Hf,Y,Cs,W,Cr,V,Li,and Pb show relative enrichment compared with UCC;Rb,Ba,Sr and Be exhibit relative depletion.The average ofΣREE is 171.91ppm with a negative anomaly forδEu and essentially no anomaly forδCe.The results of K_(2)O/Na_(2)O,Rb/Sr ratios,as well as the leaching co-efficient from three profiles,indicate DJP>JX>JZT,suggesting that DJP experiences the strongest weathering leaching effect.The chemical index of alteration(CIA)reveals that all three profiles of loess are in the primary stage of Ca and Na depletion.DJP is generally in the early to moderate stage of chemical weathering,while JX and JZT are both in the early stage. 展开更多
关键词 LOESS chemical weathering element geochemistry chemical index of alteration(CIA)
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Causal temporal graph attention network for fault diagnosis of chemical processes
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作者 Jiaojiao Luo Zhehao Jin +3 位作者 Heping Jin Qian Li Xu Ji Yiyang Dai 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第6期20-32,共13页
Fault detection and diagnosis(FDD)plays a significant role in ensuring the safety and stability of chemical processes.With the development of artificial intelligence(AI)and big data technologies,data-driven approaches... Fault detection and diagnosis(FDD)plays a significant role in ensuring the safety and stability of chemical processes.With the development of artificial intelligence(AI)and big data technologies,data-driven approaches with excellent performance are widely used for FDD in chemical processes.However,improved predictive accuracy has often been achieved through increased model complexity,which turns models into black-box methods and causes uncertainty regarding their decisions.In this study,a causal temporal graph attention network(CTGAN)is proposed for fault diagnosis of chemical processes.A chemical causal graph is built by causal inference to represent the propagation path of faults.The attention mechanism and chemical causal graph were combined to help us notice the key variables relating to fault fluctuations.Experiments in the Tennessee Eastman(TE)process and the green ammonia(GA)process showed that CTGAN achieved high performance and good explainability. 展开更多
关键词 chemical processes Safety Fault diagnosis Causal discovery Attention mechanism Explainability
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Extraction,chemical components,bioactive functions and adulteration identification of walnut oils:A review
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作者 Yuan Gao Jia Hu +6 位作者 Xia Su Qi Li Caihong Su Yongling Li Gaiqin Ma Siyu Zhang Xiuzhu Yu 《Grain & Oil Science and Technology》 CAS 2024年第1期30-41,共12页
Walnut oil is a functional wood oil known to researchers that may potentially be a large source of Chinese edible oils.There are various extraction methods for walnut oil,including traditional(pressing,solvent-and enz... Walnut oil is a functional wood oil known to researchers that may potentially be a large source of Chinese edible oils.There are various extraction methods for walnut oil,including traditional(pressing,solvent-and enzymeassisted extraction)and novel methods(microwave,ultrasound,supercritical CO_(2),subcritical and other extraction technologies).Walnut oil is rich in nutrients,including phytosterols,tocopherols,polyphenols,squalene and minerals.It provides many health benefits,such as antioxidant,antitumor,anti-inflammatory,antidiabetic and lipid metabolism-related functions.In addition,the authentication of walnut oil has received much research attention.The present review provides detailed research on walnut oil extraction,composition,health benefits and adulteration identification methods.The path toward further walnut oil improvement in the context of the market value of walnut oil is also discussed. 展开更多
关键词 Extraction technology chemical composition Bioactive AUTHENTICATION
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Plant Chemical Defenses against Insect Herbivores—Using theWild Tobacco as a Model
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作者 Guangwei Sun Xuanhao Zhang +4 位作者 Yi Liu Liguang Chai Daisong Liu Zhenguo Chen Shiyou Lü 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第4期641-659,共19页
The Nicotiana genus, commonly known as tobacco, holds significant importance as a crucial economic crop. Confrontedwith an abundance of herbivorous insects that pose a substantial threat to yield, tobacco has develope... The Nicotiana genus, commonly known as tobacco, holds significant importance as a crucial economic crop. Confrontedwith an abundance of herbivorous insects that pose a substantial threat to yield, tobacco has developed adiverse and sophisticated array of mechanisms, establishing itself as a model of plant ecological defense. Thisreview provides a concise overview of the current understanding of tobacco’s defense strategies against herbivores.Direct defenses, exemplified by its well-known tactic of secreting the alkaloid nicotine, serve as a potent toxinagainst a broad spectrum of herbivorous pests. Moreover, in response to herbivore attacks, tobacco enhancesthe discharge of volatile compounds, harnessing an indirect strategy that attracts the predators of the herbivores.The delicate balance between defense and growth leads to the initiation of most defense strategies only after aherbivore attack. Among plant hormones, notably jasmonic acid (JA), play central roles in coordinating thesedefense processes. JA signaling interacts with other plant hormone signaling pathways to facilitate the extensivetranscriptional and metabolic adjustments in plants following herbivore assault. By shedding light on these ecologicaldefense strategies, this review emphasizes not only tobacco’s remarkable adaptability in its natural habitatbut also offers insights beneficial for enhancing the resilience of current crops. 展开更多
关键词 TOBACCO HERBIVORE chemical defense jasmonic acid REGULATION
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The chemical environment and structural ordering in liquid Mg-Y-Zn system:An ab-initio molecular dynamics investigation of melt for the formation mechanism of LPSO structure
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作者 Tangpeng Ma Jin Wang +5 位作者 Kaiming Cheng Chengwei Zhan Jixue Zhou Jingyu Qin Guochen Zhao Xinfang Zhang 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第2期815-824,共10页
In an effort to clarify the formation mechanism of LPSO structure in Mg-Y-Zn alloy,the chemical environment and structural ordering in liquid Mg-rich Mg-Y-Zn system are investigated with the aid of ab-initio molecular... In an effort to clarify the formation mechanism of LPSO structure in Mg-Y-Zn alloy,the chemical environment and structural ordering in liquid Mg-rich Mg-Y-Zn system are investigated with the aid of ab-initio molecular dynamics simulation.In liquid Mg-rich Mg-Y alloys,the strong Mg-Y interaction is determined,which promotes the formation of fivefold symmetric local structure.For Mg-Zn alloys,the weak Mg-Zn interaction results in the fivefold symmetry weakening in the liquid structure.Due to the coexistence of Y and Zn,the strong attractive interaction is introduced in liquid Mg-Y-Zn ternary alloy,and contributes to the clustering of Mg,Y,Zn launched from Zn.What is more,the distribution of local structures becomes closer to that in pure Mg compared with that in binary Mg-Y and Mg-Zn alloys.These results should relate to the origins of the Y/Zn segregation zone and close-packed stacking mode in LPSO structure,which provides a new insight into the formation mechanism of LPSO structure at atomic level. 展开更多
关键词 Mg-Y-Zn chemical environment Structural ordering ab-initio molecular dynamics
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Expanding the Boundaries of the Chemical Space of DNA Methyltransferase 1 Modulators
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作者 Massyel S. Martínez-Cortés Diana L. Prado-Romero José L. Medina-Franco 《Computational Molecular Bioscience》 2024年第1期1-16,共16页
DNA methyltransferase 1 (DNMT1), one of the main epigenetic targets, is involved in the duplication of the DNA methylation pattern during replication, and it is essential for proper mammalian development. Small molecu... DNA methyltransferase 1 (DNMT1), one of the main epigenetic targets, is involved in the duplication of the DNA methylation pattern during replication, and it is essential for proper mammalian development. Small molecule DNMT1 modulators are attractive for biochemical epigenetic studies and have the potential to become drugs. So far, more than five hundred small molecules have been reported as DNMT1 inhibitors. However, only a limited number of DNMT1 activators have been disclosed because, at least in part, DNMT1 activators are typically regarded as negative data in virtual screening campaigns or optimization projects. This manuscript aims to report the chemical structures and biological activity of small molecules that increase the enzymatic activity of DNMT1. Results of the biochemical experimental assays are discussed. It was found that small molecule activators have a large variety of chemical scaffolds but share pharmacophore features. Visual analysis of the chemical space and multiverse based on molecular fingertips supported that activators are structurally diverse. This is the first report of eight small molecules that increase the enzymatic activity of DNMT1 by more than 400% in an enzymatic-based assay. The outcome warrants further investigation of the epigenetic activity of the compounds in a counter-screen assay, e.g., cell-based and in vivo context. 展开更多
关键词 chemical Multiverse CHEMOINFORMATICS EPIGENETICS Pharmacophore Hypothesis Small Molecules
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Chemical looping reforming of the micromolecular component from biomass pyrolysis via Fe_(2)O_(3)@SBA-16
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作者 Yunchang Li Bo Zhang +3 位作者 Xiantan Yang Bolun Yang Shengyong Zhang Zhiqiang Wu 《International Journal of Coal Science & Technology》 EI CAS CSCD 2024年第3期120-134,共15页
To solve the problems of low gasification efficiency and high tar content caused by solid–solid contact between biomass and oxygen carrier in traditional biomass chemical looping gasification process.The decoupling s... To solve the problems of low gasification efficiency and high tar content caused by solid–solid contact between biomass and oxygen carrier in traditional biomass chemical looping gasification process.The decoupling strategy was adopted to decouple the biomass gasification process,and the composite oxygen carrier was prepared by embedding Fe_(2)O_(3) in molecular sieve SBA-16 for the chemical looping reforming process of pyrolysis micromolecular model compound methane,which was expected to realize the directional reforming of pyrolysis volatiles to prepare hydrogen-rich syngas.Thermodynamic analysis of the reaction system was carried out based on the Gibbs free energy minimization method,and the reforming performance was evaluated by a fixed bed reactor,and the kinetic parameters were solved based on the gas–solid reaction model.Thermodynamic analysis verified the feasibility of the reaction and provided theoretical guidance for experimental design.The experimental results showed that the reaction performance of Fe_(2)O_(3)@SBA-16 was compared with that of pure Fe_(2)O_(3) and Fe_(2)O_(3)@SBA-15,and the syngas yield was increased by 55.3%and 20.7%respectively,and it had good cycle stability.Kinetic analysis showed that the kinetic model changed from three-dimensional diffusion to first-order reaction with the increase of temperature.The activation energy was 192.79 kJ/mol by fitting.This paper provides basic data for the directional preparation of hydrogen-rich syngas from biomass and the design of oxygen carriers for pyrolysis of all-component chemical looping reforming. 展开更多
关键词 Biomass pyrolysis METHANE chemical looping reforming Oxygen carrier Kinetic analysis
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Some of the Chemical and Physical Characteristics of the Graff River in Kut City, Iraq
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作者 Salih Mahdi Ali Imad Kazem Ali 《Open Journal of Modern Hydrology》 CAS 2024年第1期56-67,共12页
Some of the chemical and physical water qualities of the Graff River in the city of Kut were studied, and for two sites of the river, One was at the Crimea site, the other in the Jihad district, and for the period fro... Some of the chemical and physical water qualities of the Graff River in the city of Kut were studied, and for two sites of the river, One was at the Crimea site, the other in the Jihad district, and for the period from October/2018 to March/2019, Seven variables of river water have been analyzed: temperature PH, electrical conductivity, TDS, turbidity, alkaline, and chloride. The results showed that most of the chemical and physical water properties of the river were in normal proportions and did not rise, except for the turbidity, which was at a very high level, and that the pH values were close to the basal side. The results of the statistical analysis revealed positive significant relationships between the pH and (chloride and TDS). On the other hand, between electrical conductivity and both previous variables as well. And a negative significant connection between temperature and alkaline. 展开更多
关键词 Graff River Kut City Iraq chemical Characteristics Physical Characteristics
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Bioaccumulation,subcellular distribution and chemical forms of cadmium in Aster subulatus Michx.
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作者 LIANG Xue-lian CHEN Wei +7 位作者 JIANG Wen-yan LIAO Jie YANG Yu-xia WANG Hai-jun LI Hui-ling LU Wei-fan WANG Tian-shun XIE Hong-zhao 《南方农业学报》 CAS CSCD 北大核心 2024年第8期2386-2395,共10页
【Objective】Through analyzing the bioaccumulation capacity,subcellular distribution and chemical forms of cadmium(Cd)in Aster subulatus Michx.,this study was to provide reference for revealing the Cd tolerance mechan... 【Objective】Through analyzing the bioaccumulation capacity,subcellular distribution and chemical forms of cadmium(Cd)in Aster subulatus Michx.,this study was to provide reference for revealing the Cd tolerance mechanism of A.subulatus Michx.【Method】After cultured for 24 d under the action of Hoagland nutrient solution and gradient Cd concentrations(0,30,60 and 90 mg/L),A.subulatus Michx.were harvested,and its leaf,stem and root were treated by differential centrifugation,chemical reagent extraction,and digested with graphite digester,respectively,then the Cd content in the root,stem and leaf were determined by atomic absorption spectroscopy.【Result】The experimental results indicated that the bioaccumulation capacity of Cd in A.subulatus Michx.was root>stem>leaf,and the maximum Cd concentration in the root,stem and leaf of A.subulatus Michx.were 130.74,78.69 and 56.62 mg/kg(fresh matter),respectively.Most of Cd stored in the cell wall and the soluble fractions of the root and leaf of A.subulatus Michx.,with only a smaller portion Cd in organelle fraction.Analysis result of subcellular Cd content showed that 52.27%-58.61%of Cd for root was mainly stored in the soluble fraction,but 42.10%-63.28%of Cd for leaf was mainly stored in the cell wall fraction.The concentration of pectates and protein integrated-Cd was higher in the root and leaf compared to other chemical forms Cd.Pectates and protein integrated-Cd was the main chemical forms Cd in the root and leaf of A.subulatus Michx.,and their percentages were 68.91%-74.80%and 57.38%-83.80%,respectively.Cd treatment could significantly increase the proportion of water-soluble organic acid Cd from 13.64%to 22.72%in root and undissolved phosphate Cd from 10.02%to 32.78%in leaf with increasing Cd concentration in the culture medium.【Conclusion】The root,stem and leaf of A.subulatus Michx.has strong bioaccumulation capacity to Cd,Cd is primarily stored in the soluble fractions of the root and cell wall fractions of the leaf,and less toxic pectates and protein integrated-Cd is the main chemical forms Cd in the root and leaf of A.subulatus Michx.,this might be the main mechanism of Cd tolerance in A.subulatus Michx. 展开更多
关键词 Aster subulatus Michx. CADMIUM BIOACCUMULATION chemical form subcellular distribution
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Optimizing the sulfur-resistance and activity of perovskite oxygen carrier for chemical looping dry reforming of methane
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作者 Yuelun Li Dong Tian +6 位作者 Lei jiang Huicong Zuo LiNan Huang Mingyi Chen Jianchun Zuo Hua Wang Kongzhai Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第9期259-271,共13页
Perovskite oxides has been attracted much attention as high-performance oxygen carriers for chemical looping reforming of methane,but they are easily inactivated by the presence of trace H_(2)S.Here,we propose to modu... Perovskite oxides has been attracted much attention as high-performance oxygen carriers for chemical looping reforming of methane,but they are easily inactivated by the presence of trace H_(2)S.Here,we propose to modulate both the activity and resistance to sulfur poisoning by dual substitution of Mo and Ni ions with the Fe-sites of LaFeO_(3)perovskite.It is found that partial substitution of Ni for Fe substantially improves the activity of LaFeO_(3)perovskite,while Ni particles prefer to grow and react with H_(2)S during the long-term successive redox process,resulting in the deactivation of oxygen carriers.With the presence of Mo in LaNi_(0.05)Fe_(0.95)O_(3−σ)perovskite,H_(2)S preferentially reacts with Mo to generate MoS_(2),and then the CO_(2)oxidation can regenerate Mo via removing sulfur.In addition,Mo can inhibit the accumulation and growth of Ni,which helps to improve the redox stability of oxygen carriers.The LaNi_(0.05)Mo_(0.07)Fe_(0.88)O_(3−σ)oxygen carrier exhibits stable and excellent performance,with the CH_(4)conversion higher than 90%during the 50 redox cycles in the presence of 50 ppm H_(2)S at 800℃.This work highlights a synergistic effect in the perovskite oxides induced by dual substitution of different cations for the development of high-performance oxygen carriers with excellent sulfur tolerance. 展开更多
关键词 Perovskite oxygen carriers chemical looping reforming Sulfur-resistance Dual substitution SYNGAS
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