The thioacetamide derivative(TD)-composite preservation system(TDCPS)exhibits superior preservation effects on natural rubber latex(NRL)and significantly enhances its vulcanization efficiency and mechanical properties...The thioacetamide derivative(TD)-composite preservation system(TDCPS)exhibits superior preservation effects on natural rubber latex(NRL)and significantly enhances its vulcanization efficiency and mechanical properties.This study primarily investigated the principal chemical groups and mechanism of action of TDCPS in promoting NRL vulcanization through a comparative analysis.The results indicated that the key functional groups(thioamide and pyridine)in TDCPS synergistically accelerated crosslinking,reducing the vulcanization time by 41.18%compared to the high-ammonia(HA)preservation system.At an optimal TDCPS dosage of 5 mmol·L^(−1),vulcanized films achieved a tensile strength of 34.18 MPa,with a sulfur content of 1.5 phr further improving the strength by 42.26%.TD outperformed the conventional accelerators 2-imidazolidinethione(ETU)and 3-hydroxypyridine(3-Hp)in promoting the crosslinking density and mechanical performance while eliminating ammonia-related environmental risks.This eco-friendly system demonstrates the industrial potential for sustainable rubber production.展开更多
Objective and Impact Statement:This study aims to couple C-reactive protein(CRP)antibodies onto latex spheres of 2 different sizes to enhance the accuracy and sensitivity of CRP detection.Furthermore,it seeks to estab...Objective and Impact Statement:This study aims to couple C-reactive protein(CRP)antibodies onto latex spheres of 2 different sizes to enhance the accuracy and sensitivity of CRP detection.Furthermore,it seeks to establish a robust methodological framework crucial for advancing the development of latex-enhanced immunoturbidimetric detection reagents.Introduction:CRP,an acute-phase protein,rapidly elevates in response to infections or tissue damage.Double-particle latex-enhanced immunoturbidimetry offers important advantages for accurately measuring CRP levels.Methods:CRP antibodies were coupled with 2 sizes of polystyrene latex spheres.Coupling rates were evaluated to determine optimal conditions.Particle sizes suitable for CRP detection,as well as coupling and mixing ratios,were optimized using automated biochemical analysis.Transmission electron microscopy and nanoparticle size analysis were employed to characterize the morphology and size changes of CRP antibodies and coupled latex spheres before and after immune reaction.Results:Optimization identified 168-and 80-nm latex sphere sizes,with CRP antibody coupling rates of 92%and 91%,respectively.The optimal ratios were 10:1.5 for large latex spheres to polyclonal antibodies and 5:1.5 for small latex spheres to monoclonal antibodies.A 1:8 mixing ratio of large to small latex spheres was effective.Transmission electron microscopy confirmed uniform sizes postcoupling,maintaining dispersion with no morphological changes.CRP reacted with the double-particle latex reagent,forming immune complexes that exhibited agglutination.Mixed latex spheres showed varied agglutination states with CRP concentration,altering solution absorbance.Conclusion:This study validates the efficacy of the dual-particle-size CRP antibody latex reagent,highlighting its potential for future immunoturbidimetric analysis applications.展开更多
The environmental hazards and"carbon footprint"of oil and gas drilling can be significantly reduced by replacing traditional petroleum-based chemical additives with natural materials derived from plants and ...The environmental hazards and"carbon footprint"of oil and gas drilling can be significantly reduced by replacing traditional petroleum-based chemical additives with natural materials derived from plants and animals.This paper explored for the first time the interaction mechanism between natural rubber latex(NRL)and bentonite suspensions(BTs)through a series of characterization experiments,as well as the potential applications in water-based drilling fluids(WBDF).The gel viscoelasticity experiments showed that NRL could decrease the consistency coefficient(k)and flow index(n)of BTs,and enhance the shear thinning performance of BTs as pseudo-plastic fluids.In addition,0.5 w/v%NRL not only increased the critical yield stress and strengthened the structural strength between the bentonite particles,but also facilitated the compatibility of pressure loss and flow efficiency.The evaluation of colloidal stability and WBDF performance indicated that NRL particles could promote the hydration and charge stability on the surface of BTs particles,and optimize the particle size distribution and flow resistance of WBDF under the"intercalation-exfoliation-encapsulation"synergistic interaction.Moreover,NRL can improve the rheological properties of WBDF at high temperatures(<150.C),and form a dense blocking layer by bridging and sealing the pores and cracks of the filter cake,which ultimately reduces the permeability of the cake and the filtration loss of WBDF.展开更多
Rubber latex is an important economic resource. However, the residues from its harvesting are thrown away, even though they contain lipids that can be recycled. This recovery of the residues from the bottom of the cup...Rubber latex is an important economic resource. However, the residues from its harvesting are thrown away, even though they contain lipids that can be recycled. This recovery of the residues from the bottom of the cup requires first and foremost their characterization. The aim of this study is therefore to determine the main physical and chemical characteristics of rubber latex cup bottom oil. Oil’s physical parameters determination shows that it has a density of 951 kg∙m−3, a kinematic viscosity of 48.57 cSt and a water content of 0.0845%. Chemical parameters, meanwhile, indicate that this cup bottom residue has a fat content of 95.96%, an acid number of 2.805 mg KOH/g and an iodine number of 92.42 g I2/100g. Therefore, rubber latex cup bottom oil can be used in the formulation of biofuels, biolubricants, paints, varnishes, alkyd resins, polishing oils, soaps, and insecticides.展开更多
Most motor oils are made from mineral oils derived from petroleum, the reserves of which are limited and exhaustible. The aim of this study is to produce and characterize motor oil formulations based on mixtures of ru...Most motor oils are made from mineral oils derived from petroleum, the reserves of which are limited and exhaustible. The aim of this study is to produce and characterize motor oil formulations based on mixtures of rubber latex cup bottom oil (RLCBO) and used frying oil (UFO). The results show that these formulations have a density between 0.91 and 0.92. These densities evolve linearly with the proportion of cup bottom oil and temperature. Similarly, the kinematic viscosity of the blends follows an exponential relationship with temperature. By plotting the logarithm of these kinematic viscosities against the inverse of the temperature, we were able to determine the activation energy of the various blends and deduce that the formulations behave Newtonian.展开更多
文章以Windows操作系统为例,通过对La Te X比较常用的几种中文编辑方法进行比对分析,系统地提出La Te X编辑中文的解决办法及各自优缺点,解决了国内使用La Te X进行中文编辑排版时所遇到的困难和麻烦,使得La Te X编辑中文变得更加容易轻...文章以Windows操作系统为例,通过对La Te X比较常用的几种中文编辑方法进行比对分析,系统地提出La Te X编辑中文的解决办法及各自优缺点,解决了国内使用La Te X进行中文编辑排版时所遇到的困难和麻烦,使得La Te X编辑中文变得更加容易轻松,具有较好的实用性。展开更多
基金the Ministry of Agriculture and Rural Affairs of Chinathe Department of Science and Technology of the Hainan Province for their support+2 种基金financially supported by the National Key R&D Program of China(No. 2022YFD2301201)Hainan Province Science and Technology Special Fund (No. ZDYF2024XDNY284)Earmarked Fund for China Agriculture Research System (No.CARS-33-JG1)
文摘The thioacetamide derivative(TD)-composite preservation system(TDCPS)exhibits superior preservation effects on natural rubber latex(NRL)and significantly enhances its vulcanization efficiency and mechanical properties.This study primarily investigated the principal chemical groups and mechanism of action of TDCPS in promoting NRL vulcanization through a comparative analysis.The results indicated that the key functional groups(thioamide and pyridine)in TDCPS synergistically accelerated crosslinking,reducing the vulcanization time by 41.18%compared to the high-ammonia(HA)preservation system.At an optimal TDCPS dosage of 5 mmol·L^(−1),vulcanized films achieved a tensile strength of 34.18 MPa,with a sulfur content of 1.5 phr further improving the strength by 42.26%.TD outperformed the conventional accelerators 2-imidazolidinethione(ETU)and 3-hydroxypyridine(3-Hp)in promoting the crosslinking density and mechanical performance while eliminating ammonia-related environmental risks.This eco-friendly system demonstrates the industrial potential for sustainable rubber production.
基金supported in part by the Jilin Science and Technology Development Program(no.20220401085YY to Jiancheng Xu).
文摘Objective and Impact Statement:This study aims to couple C-reactive protein(CRP)antibodies onto latex spheres of 2 different sizes to enhance the accuracy and sensitivity of CRP detection.Furthermore,it seeks to establish a robust methodological framework crucial for advancing the development of latex-enhanced immunoturbidimetric detection reagents.Introduction:CRP,an acute-phase protein,rapidly elevates in response to infections or tissue damage.Double-particle latex-enhanced immunoturbidimetry offers important advantages for accurately measuring CRP levels.Methods:CRP antibodies were coupled with 2 sizes of polystyrene latex spheres.Coupling rates were evaluated to determine optimal conditions.Particle sizes suitable for CRP detection,as well as coupling and mixing ratios,were optimized using automated biochemical analysis.Transmission electron microscopy and nanoparticle size analysis were employed to characterize the morphology and size changes of CRP antibodies and coupled latex spheres before and after immune reaction.Results:Optimization identified 168-and 80-nm latex sphere sizes,with CRP antibody coupling rates of 92%and 91%,respectively.The optimal ratios were 10:1.5 for large latex spheres to polyclonal antibodies and 5:1.5 for small latex spheres to monoclonal antibodies.A 1:8 mixing ratio of large to small latex spheres was effective.Transmission electron microscopy confirmed uniform sizes postcoupling,maintaining dispersion with no morphological changes.CRP reacted with the double-particle latex reagent,forming immune complexes that exhibited agglutination.Mixed latex spheres showed varied agglutination states with CRP concentration,altering solution absorbance.Conclusion:This study validates the efficacy of the dual-particle-size CRP antibody latex reagent,highlighting its potential for future immunoturbidimetric analysis applications.
基金supported by the National Natural Science Foundation of China (Grant No.51991361 and Grant No.51874329)。
文摘The environmental hazards and"carbon footprint"of oil and gas drilling can be significantly reduced by replacing traditional petroleum-based chemical additives with natural materials derived from plants and animals.This paper explored for the first time the interaction mechanism between natural rubber latex(NRL)and bentonite suspensions(BTs)through a series of characterization experiments,as well as the potential applications in water-based drilling fluids(WBDF).The gel viscoelasticity experiments showed that NRL could decrease the consistency coefficient(k)and flow index(n)of BTs,and enhance the shear thinning performance of BTs as pseudo-plastic fluids.In addition,0.5 w/v%NRL not only increased the critical yield stress and strengthened the structural strength between the bentonite particles,but also facilitated the compatibility of pressure loss and flow efficiency.The evaluation of colloidal stability and WBDF performance indicated that NRL particles could promote the hydration and charge stability on the surface of BTs particles,and optimize the particle size distribution and flow resistance of WBDF under the"intercalation-exfoliation-encapsulation"synergistic interaction.Moreover,NRL can improve the rheological properties of WBDF at high temperatures(<150.C),and form a dense blocking layer by bridging and sealing the pores and cracks of the filter cake,which ultimately reduces the permeability of the cake and the filtration loss of WBDF.
文摘Rubber latex is an important economic resource. However, the residues from its harvesting are thrown away, even though they contain lipids that can be recycled. This recovery of the residues from the bottom of the cup requires first and foremost their characterization. The aim of this study is therefore to determine the main physical and chemical characteristics of rubber latex cup bottom oil. Oil’s physical parameters determination shows that it has a density of 951 kg∙m−3, a kinematic viscosity of 48.57 cSt and a water content of 0.0845%. Chemical parameters, meanwhile, indicate that this cup bottom residue has a fat content of 95.96%, an acid number of 2.805 mg KOH/g and an iodine number of 92.42 g I2/100g. Therefore, rubber latex cup bottom oil can be used in the formulation of biofuels, biolubricants, paints, varnishes, alkyd resins, polishing oils, soaps, and insecticides.
文摘Most motor oils are made from mineral oils derived from petroleum, the reserves of which are limited and exhaustible. The aim of this study is to produce and characterize motor oil formulations based on mixtures of rubber latex cup bottom oil (RLCBO) and used frying oil (UFO). The results show that these formulations have a density between 0.91 and 0.92. These densities evolve linearly with the proportion of cup bottom oil and temperature. Similarly, the kinematic viscosity of the blends follows an exponential relationship with temperature. By plotting the logarithm of these kinematic viscosities against the inverse of the temperature, we were able to determine the activation energy of the various blends and deduce that the formulations behave Newtonian.
