This paper examines the management of hazardous chemicals in Chinese university laboratories,identifying key challenges and proposing improvements.It reviews current practices and safety measures,highlighting deficien...This paper examines the management of hazardous chemicals in Chinese university laboratories,identifying key challenges and proposing improvements.It reviews current practices and safety measures,highlighting deficiencies such as inadequate safety systems and insufficient awareness among personnel.The study emphasizes the necessity of tailored safety management systems,the integration of digital tracking technologies like Radio Frequency Identification,and enhanced safety training for staff.The proposed recommendations aim to mitigate risks and enhance laboratory safety and efficiency.In conclusion,the paper asserts that a comprehensive approach,encompassing improved management systems,technological advancements,and educational initiatives,is essential for safer chemical handling in academic research environments.展开更多
The coupling effect of heat absorption and release exists in the thermal decomposition of a few chemical materials.However,the impact of the above coupling on thermal hazard assessment is not considered in the literat...The coupling effect of heat absorption and release exists in the thermal decomposition of a few chemical materials.However,the impact of the above coupling on thermal hazard assessment is not considered in the literature studies.In this work,nitroguanidine(NQ)and 1,3,5-trinitro-1,3,5-triazine(RDX)are selected as representative materials to explore the influence of the coupling effect on the thermal hazard assessment of chemical materials.The linear heating experiments of NQ and RDX are carried out by a microcalorimeter and synchronous thermal analyser.The thermal decomposition curves are decoupled by advanced thermokinetics software.The thermal decomposition and kinetic parameters before and after decoupling are calculated.The results of TG experiment show that both NQ and RDX began to lose mass during the endothermic stage.The endothermic melting and exothermic decomposition of NQ and RDX are coupled within this stage.The coupling effect has different degrees of influence on its initial decomposition temperature and safety parameters.Compared with the parameters in the coupling state,the initial decomposition temperature and adiabatic induction period after decoupling decrease.The self-accelerating decomposition temperature increases,and internal thermal runaway time decreases.In the thermal hazard assessment of chemical materials with coupling effects,the calculated parameters after decoupling should be taken as an important safety index。展开更多
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
This future article discusses the new prospects and directions of CO_(2)conversion via the photo-electrocatalytic(PEC)route.The second(2nd)generation solar fuels and chemicals(SFs)are generated directly in PEC systems...This future article discusses the new prospects and directions of CO_(2)conversion via the photo-electrocatalytic(PEC)route.The second(2nd)generation solar fuels and chemicals(SFs)are generated directly in PEC systems via electrons/protons reactions without forming molecular H_(2)as an intermediate,overcoming the thermodynamics limitations and practical issues encountered for electro-fuels produced by multistep thermocatalytic processes(i.e.CO_(2)conversion with H_(2)coming from water electrolysis).A distributed and decentralized production of SFs requires very compact,highly integrated,and intensified technologies.Among the existing reactors of advanced design(based on artificial leaves or photosynthesis),the integrated photovoltaic plus electrocatalytic(PV-EC)device is the only system(demonstrated at large scale)to produce SFs with high solar-to-fuel(STF)efficiency.However,while the literature indicates STF efficiency as the main(and only)measure of process performance,we remark here the need to refer to productivity(in terms of current density)and make tests with reliable flow PEC systems(with electrodes of at least 5–10 cm^(2))to accelerate the scaling-up process.Using approaches that minimize downstream separation costs is also mandatory.Many limitations exist in PEC systems,but most can be overcome by proper electrode and cell engineering,thus going beyond the properties of the electrocatalysts.As examples of current developments,we present the progress of(i)artificial leaf/tree devices for green H_(2)distributed production and(ii)a PEC device producing the same chemicals at both cathode and anode parts without downstream operations for green solvent distributed production.Based on these developments,future directions,such as producing fertilizers and food components from the air,are outlined.The aim is to provide new ideas and research directions from a personal perspective.展开更多
In the search of alternative resources to make commodity chemicals and transportation fuels for a low carbon future,lignocellulosic biomass with over 180-billion-ton annual production rate has been identified as a pro...In the search of alternative resources to make commodity chemicals and transportation fuels for a low carbon future,lignocellulosic biomass with over 180-billion-ton annual production rate has been identified as a promising feedstock.This review focuses on the state-of-the-art catalytic transformation of lignocellulosic biomass into value-added chemicals and fuels.Following a brief introduction on the structure,major resources and pretreatment methods of lignocellulosic biomass,the catalytic conversion of three main components,i.e.,cellulose,hemicellulose and lignin,into various compounds are comprehensively discussed.Either in separate steps or in one-pot,cellulose and hemicellulose are hydrolyzed into sugars and upgraded into oxygen-containing chemicals such as 5-HMF,furfural,polyols,and organic acids,or even nitrogen-containing chemicals such as amino acids.On the other hand,lignin is first depolymerized into phenols,catechols,guaiacols,aldehydes and ketones,and then further transformed into hydrocarbon fuels,bioplastic precursors and bioactive compounds.The review then introduces the transformations of whole biomass via catalytic gasification,catalytic pyrolysis,as well as emerging strategies.Finally,opportunities,challenges and prospective of woody biomass valorization are highlighted.展开更多
This study investigates how the debris cloud structure and hazardous fragment distribution vary with attack angle by simulating a circular cylinder projectile hypervelocity impinging on a thin plate using the finite e...This study investigates how the debris cloud structure and hazardous fragment distribution vary with attack angle by simulating a circular cylinder projectile hypervelocity impinging on a thin plate using the finite element-smoothed particle hydrodynamics(FE-SPH)adaptive method.Based on the comparison and analysis of the experimental and simulation results,the FE-SPH adaptive method was applied to address the hypervelocity yaw impact problem,and the variation law of the debris cloud structure with the attack angle was obtained.The screening criterion of the hazardous fragment at yaw impact is given by analyzing the debris formation obtained by the FE-SPH adaptive method,and the distribution characteristics of hazardous fragments and their relationship with the attack angle are given.Moreover,the velocity space was used to evaluate the distribution range and damage capability of asymmetric hazardous fragments.The maximum velocity angle was extended from fully symmetrical working conditions to asymmetrical cases to describe the asymmetrical debris cloud distribution range.In this range,the energy density was calculated to quantitatively analyze how much damage hazardous fragments inflict on the rear plate.The results showed that the number of hazardous fragments generated by the case near the 35°attack angle was the largest,the distribution range was the smallest,and the energy density was the largest.These results suggest that in this case,debris cloud generated by the impact had the strongest damage to the rear plate.展开更多
Proper waste management models using recent technologies like computer vision,machine learning(ML),and deep learning(DL)are needed to effectively handle the massive quantity of increasing waste.Therefore,waste classif...Proper waste management models using recent technologies like computer vision,machine learning(ML),and deep learning(DL)are needed to effectively handle the massive quantity of increasing waste.Therefore,waste classification becomes a crucial topic which helps to categorize waste into hazardous or non-hazardous ones and thereby assist in the decision making of the waste management process.This study concentrates on the design of hazardous waste detection and classification using ensemble learning(HWDC-EL)technique to reduce toxicity and improve human health.The goal of the HWDC-EL technique is to detect the multiple classes of wastes,particularly hazardous and non-hazardous wastes.The HWDC-EL technique involves the ensemble of three feature extractors using Model Averaging technique namely discrete local binary patterns(DLBP),EfficientNet,and DenseNet121.In addition,the flower pollination algorithm(FPA)based hyperparameter optimizers are used to optimally adjust the parameters involved in the EfficientNet and DenseNet121 models.Moreover,a weighted voting-based ensemble classifier is derived using three machine learning algorithms namely support vector machine(SVM),extreme learning machine(ELM),and gradient boosting tree(GBT).The performance of the HWDC-EL technique is tested using a benchmark Garbage dataset and it obtains a maximum accuracy of 98.85%.展开更多
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
In this research, at different quantities as fillers, Boric Acid, Calcite (CaCO<sub>3</sub>), SPT (Sodium Perborate Tetrahydrate) and as coupling matters, 3%, MAPE (Maleic Anhydride Grafted Polyethylene), ...In this research, at different quantities as fillers, Boric Acid, Calcite (CaCO<sub>3</sub>), SPT (Sodium Perborate Tetrahydrate) and as coupling matters, 3%, MAPE (Maleic Anhydride Grafted Polyethylene), Titanate and Silanyl (Vinyltriethoxysilane) were added waste paper. Composite boards were pressed and cut in 1 × 30 × 30 cm. In order to identify some properties of the produced boards, experimental works were applied according to the standards. In conclusion, bending stress reduced with filler materials and chemicals was reduced even more than the bending stress except for some experimental groups. In addition, it was observed that the coupling chemicals increased the bending strength and modulus of elasticity compared to the fillers.展开更多
The hazardous waste produced by coal-fired power plants are large in quantity and variety. It is important for ecological environment protection to properly store hazardous waste in coal-fired power plants. The enviro...The hazardous waste produced by coal-fired power plants are large in quantity and variety. It is important for ecological environment protection to properly store hazardous waste in coal-fired power plants. The environmental management of hazardous waste in coal-fired power plants started late, and there are many problems in the construction and management of their storage facilities. In this paper, taking eight typical coal-fired power plants as examples, the present problems of hazardous waste storage facilities in coal-fired power plants are analyzed, and corresponding countermeasures are put forward to solve the main common problems.展开更多
Copper(Cu)-based materials are known as the most attractive catalysts for electrochemical carbon dioxide reduction reaction(CO_(2)RR),especially the Cu^(+) species(e.g.,Cu_(2)O),which show excellent capability for cat...Copper(Cu)-based materials are known as the most attractive catalysts for electrochemical carbon dioxide reduction reaction(CO_(2)RR),especially the Cu^(+) species(e.g.,Cu_(2)O),which show excellent capability for catalyzing CO_(2) to C_(2+) chemicals because of their unique electronic structure.However,the active Cu^(+) species are prone to be reduced to metallic Cu under an electroreduction environment,thus resulting in fast deactivation and poor selectivity.Here,we developed an advanced surface modification strategy to maintain the active Cu^(+) species via assembling a protective layer of metal-organic framework(copper benzenetricarboxylate,CuBTC) on the surface of Cu_(2)O octahedron(Cu_(2)O@CuBTC).It's encouraging to see that the Cu_(2)O@CuBTC heterostructure outperforms the bare Cu_(2)O octahedron in catalyzing CO_(2) to C_(2+) chemicals and dramatically enhances the ratio of C_(2)H_(4)/CH_(4) products.A systematic study reveals that the introduced CuBTC shell plays a critical role in maintaining the active Cu^(+) species in Cu_(2)O@CuBTC heterostructure under reductive conditions.This work offers a practical strategy for improving the catalytic performance of CO_(2)RR over copper oxides and also establishes a route to maintain the state of valence-sensitive catalysts.展开更多
The Ministry of Public Security(MPS) took a nationwide concerted action of the concentrated rectification to the transpor-tation of hazardous chemicals from June 1st to June 7th.Acts in violation of laws suchas over-s...The Ministry of Public Security(MPS) took a nationwide concerted action of the concentrated rectification to the transpor-tation of hazardous chemicals from June 1st to June 7th.Acts in violation of laws suchas over-speeding of vehicles,driving with-out license and driving without escort展开更多
文摘This paper examines the management of hazardous chemicals in Chinese university laboratories,identifying key challenges and proposing improvements.It reviews current practices and safety measures,highlighting deficiencies such as inadequate safety systems and insufficient awareness among personnel.The study emphasizes the necessity of tailored safety management systems,the integration of digital tracking technologies like Radio Frequency Identification,and enhanced safety training for staff.The proposed recommendations aim to mitigate risks and enhance laboratory safety and efficiency.In conclusion,the paper asserts that a comprehensive approach,encompassing improved management systems,technological advancements,and educational initiatives,is essential for safer chemical handling in academic research environments.
基金the project of the Open Research Fund Program of Science and Technology on Aerospace Chemical Power Laboratory(Grant No.STACPL320221B04)Key Laboratory of Explosion Science and Technology(Beijing Institute of Technology)The project number is ZDKT21-01.
文摘The coupling effect of heat absorption and release exists in the thermal decomposition of a few chemical materials.However,the impact of the above coupling on thermal hazard assessment is not considered in the literature studies.In this work,nitroguanidine(NQ)and 1,3,5-trinitro-1,3,5-triazine(RDX)are selected as representative materials to explore the influence of the coupling effect on the thermal hazard assessment of chemical materials.The linear heating experiments of NQ and RDX are carried out by a microcalorimeter and synchronous thermal analyser.The thermal decomposition curves are decoupled by advanced thermokinetics software.The thermal decomposition and kinetic parameters before and after decoupling are calculated.The results of TG experiment show that both NQ and RDX began to lose mass during the endothermic stage.The endothermic melting and exothermic decomposition of NQ and RDX are coupled within this stage.The coupling effect has different degrees of influence on its initial decomposition temperature and safety parameters.Compared with the parameters in the coupling state,the initial decomposition temperature and adiabatic induction period after decoupling decrease.The self-accelerating decomposition temperature increases,and internal thermal runaway time decreases.In the thermal hazard assessment of chemical materials with coupling effects,the calculated parameters after decoupling should be taken as an important safety index。
基金The authors acknowledge the financial support from the National Natural Science Foundation of China(Grant No.32201509)Hunan Science and Technology Xiaohe Talent Support Project(2022 TJ-XH 013)+6 种基金Science and Technology Innovation Program of Hunan Province(2022RC1156,2021RC2100)State Key Laboratory of Woody Oil Resource Utilization Common Key Technology Innovation for the Green Transformation of Woody Oil(XLKY202205)State Key Laboratory of Woody Oil Resource Utilization Project(2019XK2002)Key Research and Development Program of the State Forestry and Grassland Administration(GLM[2021]95)Hunan Forestry Outstanding Youth Project(XLK202108-1)Changsha Science and Technology Project(kq2202325,kq2107022)Science and Technology Innovation Leading Talent of Hunan Province(2020RC4026).
文摘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.
基金the EU for providing support to these activities through the EU projects DECADE(862030),EPOCH(101070976)and SCOPE(810182)。
文摘This future article discusses the new prospects and directions of CO_(2)conversion via the photo-electrocatalytic(PEC)route.The second(2nd)generation solar fuels and chemicals(SFs)are generated directly in PEC systems via electrons/protons reactions without forming molecular H_(2)as an intermediate,overcoming the thermodynamics limitations and practical issues encountered for electro-fuels produced by multistep thermocatalytic processes(i.e.CO_(2)conversion with H_(2)coming from water electrolysis).A distributed and decentralized production of SFs requires very compact,highly integrated,and intensified technologies.Among the existing reactors of advanced design(based on artificial leaves or photosynthesis),the integrated photovoltaic plus electrocatalytic(PV-EC)device is the only system(demonstrated at large scale)to produce SFs with high solar-to-fuel(STF)efficiency.However,while the literature indicates STF efficiency as the main(and only)measure of process performance,we remark here the need to refer to productivity(in terms of current density)and make tests with reliable flow PEC systems(with electrodes of at least 5–10 cm^(2))to accelerate the scaling-up process.Using approaches that minimize downstream separation costs is also mandatory.Many limitations exist in PEC systems,but most can be overcome by proper electrode and cell engineering,thus going beyond the properties of the electrocatalysts.As examples of current developments,we present the progress of(i)artificial leaf/tree devices for green H_(2)distributed production and(ii)a PEC device producing the same chemicals at both cathode and anode parts without downstream operations for green solvent distributed production.Based on these developments,future directions,such as producing fertilizers and food components from the air,are outlined.The aim is to provide new ideas and research directions from a personal perspective.
文摘In the search of alternative resources to make commodity chemicals and transportation fuels for a low carbon future,lignocellulosic biomass with over 180-billion-ton annual production rate has been identified as a promising feedstock.This review focuses on the state-of-the-art catalytic transformation of lignocellulosic biomass into value-added chemicals and fuels.Following a brief introduction on the structure,major resources and pretreatment methods of lignocellulosic biomass,the catalytic conversion of three main components,i.e.,cellulose,hemicellulose and lignin,into various compounds are comprehensively discussed.Either in separate steps or in one-pot,cellulose and hemicellulose are hydrolyzed into sugars and upgraded into oxygen-containing chemicals such as 5-HMF,furfural,polyols,and organic acids,or even nitrogen-containing chemicals such as amino acids.On the other hand,lignin is first depolymerized into phenols,catechols,guaiacols,aldehydes and ketones,and then further transformed into hydrocarbon fuels,bioplastic precursors and bioactive compounds.The review then introduces the transformations of whole biomass via catalytic gasification,catalytic pyrolysis,as well as emerging strategies.Finally,opportunities,challenges and prospective of woody biomass valorization are highlighted.
基金supported by the National Natural Science Foundation of China(Grant No.11872118,11627901)。
文摘This study investigates how the debris cloud structure and hazardous fragment distribution vary with attack angle by simulating a circular cylinder projectile hypervelocity impinging on a thin plate using the finite element-smoothed particle hydrodynamics(FE-SPH)adaptive method.Based on the comparison and analysis of the experimental and simulation results,the FE-SPH adaptive method was applied to address the hypervelocity yaw impact problem,and the variation law of the debris cloud structure with the attack angle was obtained.The screening criterion of the hazardous fragment at yaw impact is given by analyzing the debris formation obtained by the FE-SPH adaptive method,and the distribution characteristics of hazardous fragments and their relationship with the attack angle are given.Moreover,the velocity space was used to evaluate the distribution range and damage capability of asymmetric hazardous fragments.The maximum velocity angle was extended from fully symmetrical working conditions to asymmetrical cases to describe the asymmetrical debris cloud distribution range.In this range,the energy density was calculated to quantitatively analyze how much damage hazardous fragments inflict on the rear plate.The results showed that the number of hazardous fragments generated by the case near the 35°attack angle was the largest,the distribution range was the smallest,and the energy density was the largest.These results suggest that in this case,debris cloud generated by the impact had the strongest damage to the rear plate.
基金the Deanship of Scientific Research at King Khalid University for funding this work underGrant Number(RGP 2/209/42)PrincessNourah bint Abdulrahman University Researchers Supporting Project Number(PNURSP2022R136)Princess Nourah bint Abdulrahman University,Riyadh,Saudi Arabia.The authors would like to thank the Deanship of Scientific Research at Umm Al-Qura University for supporting this work by Grant Code:(22UQU4210118DSR27).
文摘Proper waste management models using recent technologies like computer vision,machine learning(ML),and deep learning(DL)are needed to effectively handle the massive quantity of increasing waste.Therefore,waste classification becomes a crucial topic which helps to categorize waste into hazardous or non-hazardous ones and thereby assist in the decision making of the waste management process.This study concentrates on the design of hazardous waste detection and classification using ensemble learning(HWDC-EL)technique to reduce toxicity and improve human health.The goal of the HWDC-EL technique is to detect the multiple classes of wastes,particularly hazardous and non-hazardous wastes.The HWDC-EL technique involves the ensemble of three feature extractors using Model Averaging technique namely discrete local binary patterns(DLBP),EfficientNet,and DenseNet121.In addition,the flower pollination algorithm(FPA)based hyperparameter optimizers are used to optimally adjust the parameters involved in the EfficientNet and DenseNet121 models.Moreover,a weighted voting-based ensemble classifier is derived using three machine learning algorithms namely support vector machine(SVM),extreme learning machine(ELM),and gradient boosting tree(GBT).The performance of the HWDC-EL technique is tested using a benchmark Garbage dataset and it obtains a maximum accuracy of 98.85%.
文摘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.
文摘In this research, at different quantities as fillers, Boric Acid, Calcite (CaCO<sub>3</sub>), SPT (Sodium Perborate Tetrahydrate) and as coupling matters, 3%, MAPE (Maleic Anhydride Grafted Polyethylene), Titanate and Silanyl (Vinyltriethoxysilane) were added waste paper. Composite boards were pressed and cut in 1 × 30 × 30 cm. In order to identify some properties of the produced boards, experimental works were applied according to the standards. In conclusion, bending stress reduced with filler materials and chemicals was reduced even more than the bending stress except for some experimental groups. In addition, it was observed that the coupling chemicals increased the bending strength and modulus of elasticity compared to the fillers.
文摘The hazardous waste produced by coal-fired power plants are large in quantity and variety. It is important for ecological environment protection to properly store hazardous waste in coal-fired power plants. The environmental management of hazardous waste in coal-fired power plants started late, and there are many problems in the construction and management of their storage facilities. In this paper, taking eight typical coal-fired power plants as examples, the present problems of hazardous waste storage facilities in coal-fired power plants are analyzed, and corresponding countermeasures are put forward to solve the main common problems.
基金the Fundamental Research Funds for Central Universities (BLX202151)the National Natural Science Foundation of China (22208021, 52225003, 22109004)。
文摘Copper(Cu)-based materials are known as the most attractive catalysts for electrochemical carbon dioxide reduction reaction(CO_(2)RR),especially the Cu^(+) species(e.g.,Cu_(2)O),which show excellent capability for catalyzing CO_(2) to C_(2+) chemicals because of their unique electronic structure.However,the active Cu^(+) species are prone to be reduced to metallic Cu under an electroreduction environment,thus resulting in fast deactivation and poor selectivity.Here,we developed an advanced surface modification strategy to maintain the active Cu^(+) species via assembling a protective layer of metal-organic framework(copper benzenetricarboxylate,CuBTC) on the surface of Cu_(2)O octahedron(Cu_(2)O@CuBTC).It's encouraging to see that the Cu_(2)O@CuBTC heterostructure outperforms the bare Cu_(2)O octahedron in catalyzing CO_(2) to C_(2+) chemicals and dramatically enhances the ratio of C_(2)H_(4)/CH_(4) products.A systematic study reveals that the introduced CuBTC shell plays a critical role in maintaining the active Cu^(+) species in Cu_(2)O@CuBTC heterostructure under reductive conditions.This work offers a practical strategy for improving the catalytic performance of CO_(2)RR over copper oxides and also establishes a route to maintain the state of valence-sensitive catalysts.
文摘The Ministry of Public Security(MPS) took a nationwide concerted action of the concentrated rectification to the transpor-tation of hazardous chemicals from June 1st to June 7th.Acts in violation of laws suchas over-speeding of vehicles,driving with-out license and driving without escort
