期刊文献+
共找到11,959篇文章
< 1 2 250 >
每页显示 20 50 100
Synthesis of mordenite by solvent-free method and its application in the dimethyl ether carbonylation reaction
1
作者 Yinghui Liu Shaoduo Liu +8 位作者 Xiaosheng Wang Hongjing Wang Ranjia Li Changchun Yu Chunming Xu Yuxiang Liu Zhengqiu Xie Yongqiang Wang Pan Tang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第2期216-223,共8页
Mordenite with different Si/Al ratios were synthesized by solvent-free method and used for dimethyl ether(DME)carbonylation reaction.The influence of Si/Al ratio in the feedstock on the structure,porosity and acid sit... Mordenite with different Si/Al ratios were synthesized by solvent-free method and used for dimethyl ether(DME)carbonylation reaction.The influence of Si/Al ratio in the feedstock on the structure,porosity and acid sites were systematically investigated.The characterization results showed that with the increase of Si/Al ratio in the feedstock,part of silicon species fail to enter the skeleton and the specific surface area and pore volume of the samples decreased.The amount of weak acid and medium strong acid decreased alongside with the increasing Si/Al ratio,and the amount of strong acid slightly increased.The Al atoms preferentially enter the strong acid sites in the 8 member ring(MR)channel during the crystallization process.The high Si/Al ratio sample had more acid sites located in the 8 MR channel,leading to more active sites for carbonylation reaction and higher catalytic performance.Appropriately increasing the Si/Al ratio was beneficial for the improvement of carbonylation reaction activity over the mordenite(MOR)catalyst. 展开更多
关键词 CARBONYLATION Dimethyl ether SOLVENT-FREE ZEOLITE Synthesis CATALYSIS
下载PDF
Interfacial engineering through lead binding using crown ethers in perovskite solar cells
2
作者 Sun-Ju Kim YeonJu Kim +8 位作者 Ramesh Kumar Chitumalla Gayoung Ham Thanh-Danh Nguyen Joonkyung Jang Hyojung Cha Jovana Milić Jun-Ho Yum Kevin Sivula Ji-Youn Seo 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期263-270,共8页
In the domain of perovskite solar cells(PSCs),the imperative to reconcile impressive photovoltaic performance with lead-related issue and environmental stability has driven innovative solutions.This study pioneers an ... In the domain of perovskite solar cells(PSCs),the imperative to reconcile impressive photovoltaic performance with lead-related issue and environmental stability has driven innovative solutions.This study pioneers an approach that not only rectifies lead leakage but also places paramount importance on the attainment of rigorous interfacial passivation.Crown ethers,notably benzo-18-crown-6-ether(B18C6),were strategically integrated at the perovskite-hole transport material interface.Crown ethers exhibit a dual role:efficiently sequestering and immobilizing Pb^(2+)ions through host-guest complexation and simultaneously establishing a robust interfacial passivation layer.Selected crown ether candidates,guided by density functional theory(DFT)calculations,demonstrated proficiency in binding Pb2+ions and optimizing interfacial energetics.Photovoltaic devices incorporating these materials achieved exceptional power conversion efficiency(PCE),notably 21.7%for B18C6,underscoring their efficacy in lead binding and interfacial passivation.Analytical techniques,including time-of-flight secondary ion mass spectrometry(ToF-SIMS),ultraviolet photoelectron spectroscopy(UPS),time-resolved photoluminescence(TRPL),and transient absorption spectroscopy(TAS),unequivocally affirmed Pb^(2+)ion capture and suppression of non-radiative recombination.Notably,these PSCs maintained efficiency even after enduring 300 h of exposure to 85%relative humidity.This research underscores the transformative potential of crown ethers,simultaneously addressing lead binding and stringent interfacial passivation for sustainable PSCs poised to commercialize and advance renewable energy applications. 展开更多
关键词 Perovskite solar cells Interfacial passivation Crown ether materials Stability
下载PDF
TLC Identification and Extraction Process of Rubiasin-1-methyl Ether from Yao Medicine Chuanlianzhu
3
作者 Jingrong LU Jiangcun WEI +3 位作者 Xiumei MA Bing QING Meiyan QIU Wen ZHONG 《Medicinal Plant》 2024年第3期35-38,共4页
[Objectives]To establish a thin-layer chromatography(TLC)method for the determination of rubiadin-1-methyl ether in Yao Medicine Chuanlianzhu(Damnacanthus giganteus).[Methods]A silica gel G thin-layer plate was adopte... [Objectives]To establish a thin-layer chromatography(TLC)method for the determination of rubiadin-1-methyl ether in Yao Medicine Chuanlianzhu(Damnacanthus giganteus).[Methods]A silica gel G thin-layer plate was adopted for TLC.Petroleum ether(60-90℃)-chloroform-methanol-water(7:15:3:1)was used as the developing solvent and inspected under ultraviolet lamp(365 nm).The content was determined by Inertsil ODS-3 C 18 column(4.60 mm×250 mm,5μm),mobile phase:acetonitrile-0.2%phosphoric acid gradient elution,detection wavelength 277 nm,flow rate 1.0 mL/min,column temperature 30℃,injection volume 10μL.[Results]The spots of 10 Chuanlianzhu samples from different origins showed the same color at the same position as the control,and the spots were clear and specific.The injection volume of rubiadin-1-methyl ether showed a good linear relationship in the range of 2.90-145μg(R=0.9996).The average recovery rate of rubiadin-1-methyl ether in the low,medium and high dose groups of Yao Medicine Chuanlianzhu was 98.72%,and RSD=1.78%.[Conclusions]This method can effectively identify Yao Medicine Chuanlianzhu medicinal materials and accurately determine the content of rubiadin-1-methyl ether in the medicinal materials.It provides a scientific basis for the development and utilization of Yao Medicine Chuanlianzhu medicinal resources. 展开更多
关键词 Chuanlianzhu THIN-LAYER chromatography (TLC) Extraction process Rubiadin-1-methyl ether Content determination
下载PDF
Economy, environmental assessment and energy conservation for separation of isopropanol/diisopropyl ether/water multi-azeotropes via extractive distillation coupled pervaporation process 被引量:2
4
作者 Qinggang Xu Yasen Dai +6 位作者 Qing Zhao Zhengrun Chen Peizhe Cui Zhaoyou Zhu Yinglong Wang Jun Gao Yixin Ma 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第2期353-363,共11页
This wok proposed the extraction distillation coupled pervaporation(ED+PV) technology process using two different solvents to separate isopropanol(IPA) and diisopropyl ether(DIPE) from DIPE/IPA/H_(2)O ternary heteroge... This wok proposed the extraction distillation coupled pervaporation(ED+PV) technology process using two different solvents to separate isopropanol(IPA) and diisopropyl ether(DIPE) from DIPE/IPA/H_(2)O ternary heterogeneous azeotropes in industrial wastewater from the synthesis of isopropanol in this study.Based on strict design specifications, simulation and sequential iteration methods are used for process design and optimization. Compared to the ethylene glycol(EG)-EG+H_(2)O process and the 1,3-propanediol(PDO)-IPA+H_(2)O process, the total annual cost(TAC) of the EG-IPA+H_(2)O process decreased by 20.76% and 7.86%(PDO). Compared to the EG-EG+H_(2)O process, the TAC of the PDO-IPA+H_(2)O process reduced 14%, but the global warming potential(GWP) and human toxicity of the PDO-IPA+H_(2)O process increased 11.3% and 4.07% respectively. Compared to the PDO-IPA+H_(2)O process, the EG-IPA+H_(2)O process saves 7.86%(TAC), 9.78%(GWP) and 9.85%(human toxicity). The ED+PV process with EG is superior to PDO in factors of TAC, energy consumption, human toxicity and environment. The EG-IPA+H_(2)O process changed the separation order of the products of the multi-azeotropic system, reduced the cost and energy conservation of the system, and enhanced the environmental protection evaluation of the process, is the best process through life cycle assessment for analyzing the economy, energy conservation, environmental assessment and human toxicity, designing cleaner products, controlling waste discharge, and promoting the chemical purification industry. This work provides a new process design and optimized separation ideas, will have a good guiding significance for the research and application separation of multi-azeotropic mixture with mixed solvents in organic wastewater from the cleaner chemical production, has been up to standard wastewater discharge process, and realized the development goal of carbon peak and carbon neutrality in the sustainable development of chemical clean industry. 展开更多
关键词 Life cycle assessment Extractive distillation coupled pervaporation Isopropanol/diisopropyl ether/water azeotropes Thermodynamic efficiency Human toxicity
下载PDF
Harnessing dimethyl ether and methyl formate fuels for direct electrochemical energy conversion
5
作者 Medhanie Gebremedhin Gebru Radhey Shyam Yadav +3 位作者 Hanan Teller Haya Kornweitz Palaniappan Subramanian Alex Schechter 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第8期454-464,I0012,共12页
In this work,the oxidation of a mixture of dimethyl ether(DME) and methyl formate(MF) was studied in both an aqueous electrochemical cell and a vapor-fed polymer electrolyte membrane fuel cell(PEMFC)utilizing a multi-... In this work,the oxidation of a mixture of dimethyl ether(DME) and methyl formate(MF) was studied in both an aqueous electrochemical cell and a vapor-fed polymer electrolyte membrane fuel cell(PEMFC)utilizing a multi-metallic alloy catalyst,Pt_(3)Pd_(3)Sn_(2)/C,discovered earlier by us.The current obtained during the bulk oxidation of a DME-saturated 1 M MF was higher than the summation of the currents provided by the two fuels separately,suggesting the cooperative effect of mixing these fuels.A significant increase in the anodic charge was realized during oxidative stripping of a pre-adsorbed DME+MF mixture as compared to DME or MF individually.This is ascribed to greater utilization of specific catalytic sites on account of the relatively lower adsorption energy of the dual-molecules than of the sum of the individual molecules as confirmed by the density fu nctional theory(DFT) calculations.Fuel cell polarization was also conducted using a Pt_(3)Pd_(3)Sn_(2)/C(anode) and Pt/C(cathode) catalysts-coated membrane(CCM).The enhanced surface coverage and active site utilization resulted in providing a higher peak power density by the DME+MF mixture-fed fuel cell(123 mW cm^(-2)at 0.45 V) than with DME(84mW cm^(-2)at 0.35 V) or MF(28 mW cm^(-2)at 0.2 V) at the same total anode hydrocarbon flow rate,temperature,and ambient pressure. 展开更多
关键词 Dimethyl ether Methyl formate Fuel cell ELECTROCATALYSIS Multi-metallic alloy
下载PDF
Durable semi-crystalline interphase engineering to stabilize high voltage Ni-rich cathode in dilute ether electrolyte
6
作者 Zhuangzhuang Cui Shunqiang Chen +7 位作者 Qingshun Nian Yecheng Li Yawei Chen Bing-Qing Xiong Zihong Wang Zixu He Shuhong Jiao Xiaodi Ren 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第4期110-117,共8页
Ethers are promising electrolyte solvents for secondary Li metal batteries because of their excellent reduction stability.However,their oxidation stability has been mostly relying on the high concentration approach,an... Ethers are promising electrolyte solvents for secondary Li metal batteries because of their excellent reduction stability.However,their oxidation stability has been mostly relying on the high concentration approach,and limited progress has been made on building effective interphase to protect the cathode from the corrosion of the electrolyte.In this work,we construct a semi-crystalline interfacial layer on the surface of Li(Ni_(0.8)Co_(0.1)Mn_(0.1))O_(2)cathode that can achieve improved electrochemical stability in the highly corrosive chemical environment formed by the decomposition of ether molecules.Different from traditional brittle crystalline interphases,the optimized semi-crystalline layer with low modulus and high ionic conductivity can effectively relieve electrode strain and maintain the integrity of the interface layer.Due to this design,the continuous oxidation decomposition of ether-based electrolytes could be significantly suppressed and the battery shows outstanding cycling stability(84%capacity retention after 300 cycles).This article provides a solution to address the oxidation instability issue of ether-based electrolytes. 展开更多
关键词 Cathode/electrolyte interphase Semi-crystalline ether electrolyte High-voltage cathode Li-metal batteries
下载PDF
Butyl ether as Co-diluent in medium-concentrated electrolyte for Li-S battery
7
作者 Xirui Kong Yayun Zheng +2 位作者 Lang He Du Wang Yan Zhao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第10期343-347,I0010,共6页
1. Introduction The Lithium-sulfur battery(LSB) shows promise as a highdensity energy source, with a theoretical energy density of approximately 2600 W h kg^(-1)[1]. However, practical application of the LSB has been ... 1. Introduction The Lithium-sulfur battery(LSB) shows promise as a highdensity energy source, with a theoretical energy density of approximately 2600 W h kg^(-1)[1]. However, practical application of the LSB has been hindered by the “shuttle effect” and Li anode corrosion [2,3]. Highly concentrated electrolytes(HCEs) have been proposed as a solution, as they can inhibit the dissolution of lithium polysulfide and promote homogeneous lithium deposition [4]. 展开更多
关键词 Lithium-sulfur battery Diluted electrolyte Butyl ether Co-diluent
下载PDF
Li^(+)-ion bound crown ether functionalization enables dual promotion of dynamics and thermodynamics for ambient ammonia synthesis
8
作者 Qiyang Cheng Sisi Liu +8 位作者 Mengfan Wang Lifang Zhang Yanzheng He Jiajie Ni Jingru Zhang Chengwei Deng Yi Sun Tao Qian Chenglin Yan 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第10期191-197,I0007,共8页
Electrosynthesis of ammonia from the reduction of nitrogen is still confronted with the limited supply of gas reactant in dynamics as well as high activation barrier in thermodynamics.Unfortunately,despite tremendous ... Electrosynthesis of ammonia from the reduction of nitrogen is still confronted with the limited supply of gas reactant in dynamics as well as high activation barrier in thermodynamics.Unfortunately,despite tremendous efforts devoted to electrocatalysts themselves,they still fail to tackle the above two challenges simultaneously.Herein,we employ a heterogeneous catalyst adlayer-composed of crown ethers associated with Li^(+)ions-to achieve the dual promotion of dynamics and thermodynamics for ambient ammonia synthesis.Dynamically,the bound Li^(+)ions interact with the strong quadrupole moment of nitrogen,and trigger considerable reactant flux toward the catalyst.Thermodynamically,Li^(+)associated with the oxygen of crown ether achieves a higher density of states at the Fermi level for the catalyst,enabling effortless electron transfer from the catalysts to nitrogen and thus greatly reducing the activation barrier.As expected,the proof-of-concept system achieves an ammonia yield rate of 168.5μg h^(-1)mg^(-1)and a Faradaic efficiency of 75.3%at-0.3 V vs.RHE.This system-level approach opens up pathways for tackling the two key challenges that have limited the field of ammonia synthesis. 展开更多
关键词 Li^(+)-ion bound crown ether DYNAMICS Thermodynamics Nitrogen reduction Ammonia synthesis
下载PDF
Density Functional Theory Study of Marine Polybrominated Diphenyl Ethers in Anaerobic Degradation
9
作者 XU Xiang MAN Miaomiao +3 位作者 SUN Qinxing LIU Qingzhi WU Kechen YANG Dengfeng 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第5期1353-1360,共8页
Polybrominated diphenyl ethers(PBDEs)are a kind of serious pollutants in the ocean.Biodegradation is considered as an economical and safe way for PBDEs removal and reductive debromination dominates the initial pathway... Polybrominated diphenyl ethers(PBDEs)are a kind of serious pollutants in the ocean.Biodegradation is considered as an economical and safe way for PBDEs removal and reductive debromination dominates the initial pathway of anaerobic degradation.On the basis of experimental study,Octa-BDE 197,Hepta-BDE 183,Hexa-BDE 153,Penta-BDE 99 and Tetra-BDE 47 were selected as the initial degradation objects,and their debromination degradation were studied using density functional theory.The structures were optimized by Gaussian 09 program.Furthermore,the molecular orbitals and charge distribution were analyzed.All C-Br bond dissociation energies at different positions including ortho,meta and para bromine atoms were calculated and the sequence of debromination was obtained.There is a close relationship between molecular structure,charge,molecular orbital and C-Br bond.All PBDEs exhibited similar debromination pathways with preferential removal of meta and para bromines. 展开更多
关键词 polybrominated diphenyl ethers reductive debromination anaerobic degradation density functional theory bond dissociation energies
下载PDF
Functional zirconium phosphate nanosheets enabled transfer hydrogenolysis of aromatic ether bonds over a low usage of Ru nanocatalysts
10
作者 Jinliang Song Yayun Pang +2 位作者 Chenglei Xiao Huizhen Liu Buxing Han 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第5期373-380,I0009,共9页
Catalytic hydrogenolysis of aromatic ether bonds is a highly promising strategy for upgrading lignin into small-molecule chemicals,which relies on developing innovative heterogeneous catalysts with high activity.Herei... Catalytic hydrogenolysis of aromatic ether bonds is a highly promising strategy for upgrading lignin into small-molecule chemicals,which relies on developing innovative heterogeneous catalysts with high activity.Herein,we designed porous zirconium phosphate nanosheet-supported Ru nanocatalysts(Ru/ZrPsheet)as the heterogeneous catalyst by a process combining ball milling and molten-salt(KNO_(3)).Very interestingly,the fabricated Ru/ZrPsheetshowed good catalytic performance on the transfer hydrogenolysis of various types of aromatic ether bonds contained in lignin,i.e.,4-O-5,a-O-4,β-O-4,and aryl-O-CH3,over a low Ru usage(<0.5 mol%)without using any acidic/basic additive.Detailed investigations indicated that the properties of Ru and the support were indispensable.The excellent activity of Ru/ZZrPsheetoriginated from the strong acidity and basicity of ZrPsheetand the higher electron density of metallic Ru0as well as the nanosheet structure of ZrPsheet. 展开更多
关键词 Valorization of lignin Aromatic ether bonds Transfer hydrogenolysis synergistic cooperation Zirconium phosphate nanosheets
下载PDF
Concentrated ternary ether electrolyte allows for stable cycling of a lithium metal battery with commercial mass loading high-nickel NMC and thin anodes
11
作者 Jun Yang Xing Li +17 位作者 Ke Qu Yixian Wang Kangqi Shen Changhuan Jiang Bo Yu Pan Luo Zhuangzhi Li Mingyang Chen Bingshu Guo Mingshan Wang Junchen Chen Zhiyuan Ma Yun Huang Zhenzhong Yang Pengcheng Liu Rong Huang Xiaodi Ren David Mitlin 《Carbon Energy》 SCIE CSCD 2023年第3期2-18,共17页
A new concentrated ternary salt ether-based electrolyte enables stable cycling of lithium metal battery(LMB)cells with high-mass-loading(13.8 mg cm^(−2),2.5 mAh cm^(−2))NMC622(LiNi_(0.6)Co_(0.2)Mn_(0.2)O_(2))cathodes ... A new concentrated ternary salt ether-based electrolyte enables stable cycling of lithium metal battery(LMB)cells with high-mass-loading(13.8 mg cm^(−2),2.5 mAh cm^(−2))NMC622(LiNi_(0.6)Co_(0.2)Mn_(0.2)O_(2))cathodes and 50μm Li anodes.Termed“CETHER-3,”this electrolyte is based on LiTFSI,LiDFOB,and LiBF4 with 5 vol%fluorinated ethylene carbonate in 1,2-dimethoxyethane.Commer-cial carbonate and state-of-the-art binary salt ether electrolytes were also tested as baselines.With CETHER-3,the electrochemical performance of the full-cell battery is among the most favorably reported in terms of high-voltage cycling stability.For example,LiNi_(x)Mn_(y)Co_(1-x-y)O_(2)(NMC)-Li metal cells retain 80%capacity at 430 cycles with a 4.4 V cut-off and 83%capacity at 100 cycles with a 4.5 V cut-off(charge at C/5,discharge at C/2).According to simulation by density functional theory and molecular dynamics,this favorable performance is an outcome of enhanced coordination between Li^(+)and the solvent/salt molecules.Combining advanced microscopy(high-resolution transmission electron microscopy,scanning electron microscopy)and surface science(X-ray photoelectron spectroscopy,time-of-fight secondary ion mass spectroscopy,Fourier-transform infrared spectroscopy,Raman spectroscopy),it is demonstrated that a thinner and more stable cathode electrolyte interphase(CEI)and solid electrolyte interphase(SEI)are formed.The CEI is rich in lithium sulfide(Li_(2)SO_(3)),while the SEI is rich in Li_(3)N and LiF.During cycling,the CEI/SEI suppresses both the deleterious transformation of the cathode R-3m layered near-surface structure into disordered rock salt and the growth of lithium metal dendrites. 展开更多
关键词 concentrated electrolyte density functional theory ether electrolyte high‐nickel cathode high‐voltage battery molecular dynamics
下载PDF
A Comparative Study of the Hydroxyl Value and Iodine Value in Polyoxyl Stearyl Ether in United States Pharmacopeia Specifications
12
作者 Alyssa Beres Yusuf Yildiz 《American Journal of Analytical Chemistry》 2023年第9期410-419,共10页
The iodine value (iodine number) and hydroxyl value are important analytical characteristics of fats and oils. The iodine (I<sub>2</sub>) required saturating the fatty acids present in 100 grams of the oil... The iodine value (iodine number) and hydroxyl value are important analytical characteristics of fats and oils. The iodine (I<sub>2</sub>) required saturating the fatty acids present in 100 grams of the oil or fat. Iodine value is a measure of the total number of double bonds (-C=C-) present in fats and oils. Unsaturated compounds contain molecules with double and triple bonds which are very reactive towards iodine. The iodine value has been determined according to Hanus with iodine monobromide in glacial acetic acid, and then the amount of iodine remaining unreacted is determined by titration using sodium thiosulfate volumetric standard solution. The hydroxyl value is the amount of potassium hydroxide in milligrams that is equivalent to the hydroxyl amount of 1 gram of the sample (mg KOH/g sample). Poloxyl Stearyl Ether is a mixture of the monostearyl ethers of mixed polyethylene glycols. It may contain various amounts of free stearyl alcohol and some free polyethylene glycol. In this study, the iodine value and hydroxyl value have been determined by titration in polyoxyl stearyl ether. Iodine value 1.84 g of I<sub>2</sub> absorbed/100g sample, and hydroxyl value 162.65 mg KOH/g sample have been found in poloxyl stearyl ether. The iodine value and hydroxyl value results met the United States Pharmacopeia specifications for Polyoxyl Stearyl Ether. 展开更多
关键词 Iodine Value Hydroxyl Value Hanus Method Polyoxyl Stearyl ether
下载PDF
2,4-Dinitrophenyl Ether of Polyvinyl Alcohol and Polymer Bound Anionic SIGMA Complexes
13
作者 John C. Phelan Michael J. Strauss 《International Journal of Organic Chemistry》 2023年第3期87-95,共9页
A new electrophilic polymer, 2,4-dinitrophenyl ether of polyvinyl alcohol (PVA-DNP), having a degree of substitution of 0.5 was prepared from polyvinyl alcohol (PVA) and 1-fluro-2,4-dinitrobenzene (DNFB). The PVA-DNP ... A new electrophilic polymer, 2,4-dinitrophenyl ether of polyvinyl alcohol (PVA-DNP), having a degree of substitution of 0.5 was prepared from polyvinyl alcohol (PVA) and 1-fluro-2,4-dinitrobenzene (DNFB). The PVA-DNP polymer was characterized by NMR, IR, and UV-visible spectroscopy. The reaction of PVA-DNP with sodium methoxide was followed by NMR and UV-visible spectroscopy. Evidence of polymer bound spirocyclic SIGMA complex, C-1 and C-3 polymer bound DNP-methoxy SIGMA complexes and the formation and C-1 methoxy complex of 2,4-dinitroanisole was observed. 展开更多
关键词 2 4-Dinitrophenyl ether Polyvinyl Alcohol Anionic SIGMA Complex Thermal Stability Nucleophilic Aromatic Substitution
下载PDF
Ether as the Fundamental Substance of the Creation of the Universe
14
作者 Avas Khugaev Eugeniya Bibaeva 《Journal of Applied Mathematics and Physics》 2023年第12期3800-3825,共26页
The paper analyzes the concept of Ether and substantiates the necessity of its existence as a physical reality, which arises within the framework of the concept developed by the authors of the work. The authors come t... The paper analyzes the concept of Ether and substantiates the necessity of its existence as a physical reality, which arises within the framework of the concept developed by the authors of the work. The authors come to the conclusion that the existence of Ether in two different forms, plays an exceptional role in the formation of Dark Matter and Dark Energy and leads to the emergence of exotic cosmological structures and their hierarchy in energy, temporal, and spatial scale. The mechanism of the formation of physical structures before the Big Bang and their further evolution, up to the formation of worlds of galaxies and stars, is considered. The necessity of the emergence of exotic structures, such as 3 spheres of the Primary Relict, is shown, its structure and dynamic properties leading to the formation of Order from Chaos are considered. The role of the 1st and 2nd type Ether in the formation of the mechanism of transformation of cosmic energies and quantum phase transitions, in the process of the birth and evolution of the Universe is discussed. The conclusion is made about the existence of universal properties of matter, at the level of Macro and Microcosms, and a multidimensional cosmological model with an isothermal temperature distribution is constructed, leading to a discrete distribution of matter separated by transitions, by analogy with Black-and-White Holes. It is shown that the postulate of the constancy of the speed of light in any inertial system is a consequence of the principle of covariance. 展开更多
关键词 ether Speed of Light Black and White Hole Quantum Transitions Primary Relict Chaos and Order Primary Atom Big Bang Dark Matter and Energy Borromeo Rings
下载PDF
The Quantum Chromodynamics Gas Density Drop and the General Theory of Relativity Ether
15
作者 Rami Rom 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2023年第2期445-454,共10页
β decay is one of the most fundamental and thoroughly studied nuclear decay. Surprisingly, the β decay rates were found to have a periodic time variability [1]. However, others argued that there is no evidence for s... β decay is one of the most fundamental and thoroughly studied nuclear decay. Surprisingly, the β decay rates were found to have a periodic time variability [1]. However, others argued that there is no evidence for such cyclic deviation from the exponential first order kinetics decay law [2]. Here we propose that the β decay is a pseudo-first order exchange reaction triggered by udd&utilde;exotic mesons and propose a QCD gas theory. In analogy to the atmospheric gas density, the proposed QCD gas density drops with elevation from the sun. Accordingly, we propose that the β decay rate periodic variability is due to the pseudo-first order exchange reaction kinetics and the QCD gas atmospheric density drop. The proposed QCD gas may be a possible candidate for Einstein’s general theory of relativity ether [3]. Our main results are the derived formulas for calculating the effective mass of the QCD gas and the cosmology perfect fluid equation of state dimensionless parameter, based on the measured ratio of the β decay rates at the earth trajectory aphelion and perihelion dates. . 展开更多
关键词 Nuclear Decay β Decay Rate Variability Atmospheric Density Quantum Chromodynamics (QCD) Exotic Mesons General Theory of Relativity (GR) ether Dark Energy
下载PDF
ABPBI/SPEEK高温质子交换复合膜的制备与表征 被引量:1
16
作者 张琪 陆婕妤 +1 位作者 钟璟 郭向前 《现代化工》 CAS CSCD 北大核心 2024年第2期91-96,共6页
采用溶剂蒸发法制备聚(2,5-苯并咪唑)/磺化聚醚醚酮(ABPBI/SPEEK)高温质子交换复合膜。考察了SPEEK的掺入对ABPBI/SPEEK质子交换复合膜的结构及性能的影响。结果表明,ABPBI膜和ABPBI/SPEEK复合膜在高温下的热稳定性能良好;随着SPEEK的掺... 采用溶剂蒸发法制备聚(2,5-苯并咪唑)/磺化聚醚醚酮(ABPBI/SPEEK)高温质子交换复合膜。考察了SPEEK的掺入对ABPBI/SPEEK质子交换复合膜的结构及性能的影响。结果表明,ABPBI膜和ABPBI/SPEEK复合膜在高温下的热稳定性能良好;随着SPEEK的掺入,ABPBI/SPEEK复合膜有更好的氧化稳定性和机械性能,ABPBI/SPEEK(20%)复合膜在芬顿试剂中96 h后的质量损失为0.84%,其拉伸强度为120.51 MPa,相较于Nafion 117膜明显提高;ABPBI/SPEEK(20%)复合膜的酸掺杂率为186.68%,该膜在160℃、0%RH时的质子电导率为3.4 mS/cm,约为ABPBI膜的1.78倍。 展开更多
关键词 聚(2 5-苯并咪唑) 磺化聚醚醚酮 质子交换膜 高温 质子电导率
下载PDF
基于整合生物标志物法评价十溴联苯醚对紫红笛鲷肝脏的氧化胁迫效应
17
作者 张喆 陈海刚 +2 位作者 田斐 张林宝 蔡文贵 《生态科学》 CSCD 北大核心 2024年第3期11-19,共9页
研究了不同浓度十溴联苯醚(decabromodiphenyl ether,BDE209)对紫红笛鲷肝脏抗氧化酶和药物代谢酶的影响,并采用整合生物标志物法综合评价BDE209对紫红笛鲷肝脏的氧化胁迫效应。结果表明:BDE209胁迫3—7 d,紫红笛鲷肝脏超氧化物歧化酶(s... 研究了不同浓度十溴联苯醚(decabromodiphenyl ether,BDE209)对紫红笛鲷肝脏抗氧化酶和药物代谢酶的影响,并采用整合生物标志物法综合评价BDE209对紫红笛鲷肝脏的氧化胁迫效应。结果表明:BDE209胁迫3—7 d,紫红笛鲷肝脏超氧化物歧化酶(superoxide dismutase,SOD)、过氧化氢酶(catalase,CAT)、过氧化物酶(peroxidase,POD)和谷胱甘肽硫转移酶(glutathione S-transferase,GST)活性显著升高,但并未呈现明显的剂量效应。胁迫30 d时,上述酶活性与对照组没有显著差异。BDE209胁迫下,紫红笛鲷肝脏细胞色素P450(cytochromeP450,P450)含量先降低后升高,而细胞色素b5(cytochromeb5,b5)含量则呈先升高后下降的趋势。上述结果表明BDE209可能引起了紫红笛鲷肝脏细胞发生氧化应激反应。BDE209胁迫第7 d时,IBR值最大。各实验组IBR均高于对照组,且随着BDE209浓度的升高,IBR值逐渐增大。与其他指标相比,POD活性、P450和b5含量可作为BDE209胁迫的潜在生物标志物,IBR方法可被应用于评价环境浓度BDE209对紫红笛鲷胁迫的毒性效应,对于综合评价BDE209对生物体的生态毒理效应具有重要意义。 展开更多
关键词 十溴联苯醚 紫红笛鲷 整合生物标志物 抗氧化酶
下载PDF
一种新型的用于萃取铷的冠醚功能化磁性固相纳米材料
18
作者 付华 陈慧媛 +1 位作者 宋维君 赵云 《材料导报》 EI CAS CSCD 北大核心 2024年第17期278-283,共6页
本研究成功制备了一种新型的用于萃取铷的冠醚功能化磁性固相纳米材料(CFE)。通过溶剂热法合成了Fe_(3)O_(4)纳米颗粒磁核,利用3-氨丙基三乙氧基硅烷在碱性环境下的酯水解反应,在磁核表面包覆SiO_(2)并修饰氨基,制备了Fe_(3)O_(4)@SiO_(... 本研究成功制备了一种新型的用于萃取铷的冠醚功能化磁性固相纳米材料(CFE)。通过溶剂热法合成了Fe_(3)O_(4)纳米颗粒磁核,利用3-氨丙基三乙氧基硅烷在碱性环境下的酯水解反应,在磁核表面包覆SiO_(2)并修饰氨基,制备了Fe_(3)O_(4)@SiO_(2)-NH_(2)中间产物,再利用4′-羧基苯并-18-冠6-醚上的羧基与修饰在Fe_(3)O_(4)@SiO_(2)-NH_(2)表面的氨基在1-乙基-(3-二甲基氨基丙基)碳二亚胺盐酸盐的催化下发生酰胺化反应,将该冠醚修饰在中间产物的表面,制备了CFE新型材料。分析了Fe_(3)O_(4)、Fe_(3)O_(4)@SiO_(2)-NH_(2)、CFE的微观形貌、磁化性质、X射线衍射性质、红外吸收性质、元素组成,佐证了材料被成功制备,验证了CFE对Rb^(+)的萃取能力,研究了溶液pH对Rb^(+)萃取效果的影响。结果表明,室温下萃取30 min,在pH为13时CFE对Rb^(+)具有最佳的萃取效果,萃取率为90.0%。 展开更多
关键词 磁性固相萃取 冠醚 功能材料 纳米材料
下载PDF
三次采油用月桂醇聚氧乙烯醚非离子表面活性剂的高效液相色谱分析检测方法
19
作者 温静 肖传敏 +2 位作者 张艳娟 王立成 郭勇 《油田化学》 CAS CSCD 北大核心 2024年第3期537-542,共6页
为了建立三次采油用月桂醇聚氧乙烯醚非离子表面活性剂的液相色谱分析检测方法,通过对色谱要素的优化实验,确立了最佳色谱条件,并进行了方法学评价。实验确定色谱柱为羟基柱,规格为150 mm×4.6 mm;流动相为乙腈与水;梯度洗脱(0~3 mi... 为了建立三次采油用月桂醇聚氧乙烯醚非离子表面活性剂的液相色谱分析检测方法,通过对色谱要素的优化实验,确立了最佳色谱条件,并进行了方法学评价。实验确定色谱柱为羟基柱,规格为150 mm×4.6 mm;流动相为乙腈与水;梯度洗脱(0~3 min:25%乙腈/75%水;3~8 min:90%乙腈/10%水;8.01 min:25%乙腈/75%水);流速为1.0 mL/min;质谱检测器正模式检测;进样量为2μL。该方法在20~200 mg/L浓度范围内线性相关系数R=0.99998,检出限低至5 mg/L,加标回收率在88.10%~97.14%之间,10 min完成一次分析,展现了检测结果准确、检测方法灵敏、快速的色谱学优点,能够满足复杂采出液中月桂醇聚氧乙烯醚非离子表面活性剂的定量检测。因采用质谱检测器,可同时开展油井采出液中月桂醇聚氧乙烯醚非离子表面活性剂的结构鉴定。 展开更多
关键词 月桂醇聚氧乙烯醚 非离子表面活性剂 高效液相色谱 质谱 三次采油
下载PDF
防风石油醚提取物调节中性粒细胞胞外诱捕网对类风湿性关节炎大鼠的改善作用及机制
20
作者 张向阳 魏薇 +5 位作者 徐鹏 李宁 葛文静 王新义 梁瑞峰 薛爱荣 《中国药房》 CAS 北大核心 2024年第19期2345-2351,共7页
目的 探究防风石油醚提取物通过调节中性粒细胞胞外诱捕网(NETs)对类风湿性关节炎(RA)大鼠的改善作用及机制。方法 采用牛Ⅱ型胶原与弗氏完全佐剂建立大鼠RA模型。将造模成功的大鼠随机分为模型组和防风石油醚提取物低、中、高剂量组(55... 目的 探究防风石油醚提取物通过调节中性粒细胞胞外诱捕网(NETs)对类风湿性关节炎(RA)大鼠的改善作用及机制。方法 采用牛Ⅱ型胶原与弗氏完全佐剂建立大鼠RA模型。将造模成功的大鼠随机分为模型组和防风石油醚提取物低、中、高剂量组(55、110、220 mg/kg),另设不造模的正常组,每组10只。各组大鼠灌胃相应药液或等体积2%吐温-80溶液,每天1次,连续28 d。观察大鼠足趾肿胀度并进行关节炎指数(AI)评分,检测大鼠血清中白细胞介素1β(IL-1β)、IL-10、IL-17、肿瘤坏死因子α(TNF-α)、25-羟基维生素D_3[25(OH)D_3]、髓过氧化物酶(MPO)、中性粒细胞弹性蛋白酶(NE)和NETs的水平,观察大鼠踝关节病理学形态变化,检测大鼠踝关节中瓜氨酸化组蛋白H3(CitH3)以及滑膜组织中细胞色素P450 24A1(CYP24A1)、细胞色素P45027B1(CYP27B1)、维生素D受体(VDR)、肽基精氨酸脱亚胺酶4(PAD4)的表达水平。结果 与模型组比较,防风石油醚提取物中、高剂量组大鼠给药后第14天至第28天的足趾肿胀度和AI评分均显著降低(P<0.05或P<0.01);血清中IL-1β、IL-17、TNF-α、MPO、NE和NETs水平均显著降低,IL-10、25(OH)D_3水平均显著升高(P<0.05或P<0.01);踝关节间隙变宽,结构明显改善;踝关节中CitH3以及滑膜组织中CYP24A1、PAD4表达水平均显著降低,滑膜组织中CYP27B1、VDR表达水平均显著升高(P<0.05或P<0.01)。结论 防风石油醚提取物可能通过调控维生素D系统,抑制NETs生成,进而改善RA症状。 展开更多
关键词 类风湿性关节炎 防风 石油醚提取物 维生素D 中性粒细胞胞外诱捕网 炎症因子
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部