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Synthesis, Crystal Structure and Fungicidal Activity of (Z)-3,3-Dimethyl-1-(1H-1,2,4-triazol-1-yl)butan-2-one O-2-Chlorobenzyl Oxime Nitrate 被引量:2
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作者 叶姣 玄文静 胡艾希 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第9期1265-1268,共4页
The title compound has been synthesized by the reaction of 3,3-dimethyl-1-(1H-1,2,4-triazol-1-yl)butan-2-one oxime with 2-chlorobenzyl chloride, and then treated with 65~68% HNO3. Its crystal structure was determin... The title compound has been synthesized by the reaction of 3,3-dimethyl-1-(1H-1,2,4-triazol-1-yl)butan-2-one oxime with 2-chlorobenzyl chloride, and then treated with 65~68% HNO3. Its crystal structure was determined by single-crystal X-ray diffraction. The crystal belongs to the monoclinic system, space group P21/c with a = 14.5481(8), b = 9.3351(5), c = 13.1911(7) , β = 98.9450(10)°, Z = 4, V = 1769.67(17) 3, Mr = 369.81, Dc = 1.388 g/cm3, S = 1.06, μ = 0.247 mm-1, F(000) = 776, the final R = 0.0352 and wR = 0.0960 for 3069 observed reflections (I 2σ(I)). X-ray crystal structure presents the intramolecular N–H…O hydrogen bond. The packing is nearly parallel without π-π stacking interactions between two adjacent phenyl rings and stabilized by Van der Waals force. The preliminary bioassay shows that the title compound possesses fungicidal activity against Gibberella zeae at the dosage of 25 mg/L. 展开更多
关键词 (Z)-3 3-dimethyl-1-(1H-1 2 4-triazol-1-yl)butan-2-one O-2-chlorobenzyl oxime nitrate crystal structure synthesis fungicidal activity
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The Solvent Effect on the Chemoselectivity of Palladium-catalyzed Oligomerization of 3,3-Dimethyl-1-butyne 被引量:1
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作者 JinShengCHENG JinHengLI +1 位作者 HuanFengJIANG XiaoYueOUYANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第9期966-968,共3页
The chemoselectivities of PdCl2 and CuCl2-catalyzed oligomerization of 3, 3-dimethyl-butyne: 1, 3, 5-tri-tert-butylbenzene, 2, 2, 7, 7-tetramethyl-3, 6-dichloro-3, 5-octadiene and 2, 2, 7, 7- tetramethyl-3, 5-octadiyn... The chemoselectivities of PdCl2 and CuCl2-catalyzed oligomerization of 3, 3-dimethyl-butyne: 1, 3, 5-tri-tert-butylbenzene, 2, 2, 7, 7-tetramethyl-3, 6-dichloro-3, 5-octadiene and 2, 2, 7, 7- tetramethyl-3, 5-octadiyne were obtained, respectively, by regulating the polarity of the solvent. 展开更多
关键词 Solvent CHEMOSELECTIVITY palladium OLIGOMERIZATION 3 3-dimethyl-1-butyne.
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Synthesis,Crystal Structure and Plant Growth Regulatory Activity of 1-(3-Amino-[1,2,4]triazol-1-yl)-3,3-dimethyl-butan-2-one 被引量:1
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作者 蔡光容 郑殿峰 +1 位作者 李冰 冯乃杰 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第4期599-604,共6页
The title compound 1-(3-amino-[1,2,4]triazol-1-yl)-3,3-dimethyl-butan-2-one(3) was synthesized by Hofmann-alkylation reaction of 1-chloro-3,3-dimethyl-butan-2-one(1) and ~1H-[1,2,4]triazol-3-ylamine(2) with eq... The title compound 1-(3-amino-[1,2,4]triazol-1-yl)-3,3-dimethyl-butan-2-one(3) was synthesized by Hofmann-alkylation reaction of 1-chloro-3,3-dimethyl-butan-2-one(1) and ~1H-[1,2,4]triazol-3-ylamine(2) with equal amount of K_2CO_3 as acid acceptor. The structure of compound 3 was characterized by ~1H NMR, 13 C NMR, HRMS and single-crystal X-ray diffraction. The compound crystallizes in the monoclinic system, space group P21/n with a = 5.7227(8), b = 27.924(4), c = 6.2282(7) ?, β = 101.892(11)°, V = 973.9(2) ?~3, Z = 4, T = 180.00(10) K, μ(MoKα) = 0.087 mm^(-1), Dc = 1.243 g/cm^3, 3832 reflections measured(3.648≤θ≤26.022°), 1916 unique reflections(Rint = 0.0359, Rsigma = 0.0572) used in all calculations. The final R = 0.0557(I 〉 2σ(I)) and w R = 0.1276(all data). Bioassay showed that 3 displayed excellent activity as plant growth regulator with inducing lateral root formation and enhancing primary root elongation at 0.27 mmol/L(50 ppm) in soybeen(He Feng-50). Good water solubility was found with 50 mg in 1 m L of water. Therefore, application of 3 in agriculture is more environmentally friendly due to cosolvent-free condition, and results in improved abiotic-stress tolerance by affecting the root growth. And furthermore, it can be used as a precursor to investigate the function of regulating plant root growth. 展开更多
关键词 1-(3-amino-[1 2 4]triazol-1-yl)-3 3-dimethyl-butan-2-one crystal structure synthesis plant growth regulator
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A Novel Photoproduct of 1, 3-Dimethyluracil in Phosphate Buffered-saline
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作者 Feng LIN Shao Yong BAI 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第9期1158-1160,共3页
1, 3-Dimethyluracil (DMU) in phosphate buffered-saline (PBS, pH=8) was irradiated by a medium pressure mercury lamp (MPML) and produced a novel compound C6H9N2O6P. The composition and structure of the compound h... 1, 3-Dimethyluracil (DMU) in phosphate buffered-saline (PBS, pH=8) was irradiated by a medium pressure mercury lamp (MPML) and produced a novel compound C6H9N2O6P. The composition and structure of the compound has been identified by elemental analysis, EIMS, UV, IR, ^1H and ^31P-NMR. 展开更多
关键词 UV Photolysis 1 3-dimethyluracil phosphate buffered-saline(PBS)
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Severe liver injury and clinical characteristics of occupational exposure to 2-amino-5-chloro-N,3-dimethylbenzamide: A case series 被引量:1
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作者 Meng-Xiao Feng Hua Zou Yuan-Qiang Lu 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2024年第2期186-194,共9页
Background:The 2-amino-5-chloro-N,3-dimethylbenzamide is a key intermediate in the synthesis of pesticides and pharmaceuticals.However,no literature currently exists on 2-amino-5-chloro-N,3-dimethylbenzamide poisoning... Background:The 2-amino-5-chloro-N,3-dimethylbenzamide is a key intermediate in the synthesis of pesticides and pharmaceuticals.However,no literature currently exists on 2-amino-5-chloro-N,3-dimethylbenzamide poisoning in humans.This study aimed to reveal the health hazard of this chemical for humans and summarize the clinical characteristics of patients with occupational 2-amino-5-chloro-N,3-dimethylbenzamide poisoning.Methods:This observational study included four patients with 2-amino-5-chloro-N,3-dimethylbenzamide poisoning from June 2022 to July 2022.The entire course of the incidents was described in detail.Blood 2-amino-5-chloro-N,3-dimethylbenzamide concentrations were detected by a mass spectrometer.Hema-toxylin and eosin staining was performed to assess liver injury,and immunofluorescence was used to evaluate hepatic mitophagy.Results:The 2-amino-5-chloro-N,3-dimethylbenzamide powder(99%purity)entered the human body mainly via the skin and respiratory tract due to poor personal protective measures.The typical course of 2-amino-5-chloro-N,3-dimethylbenzamide poisoning was divided into latency,rash,fever,organic dam-age,and recovery phases in accordance with the clinical evolution.Rash and fever may be the important premonitory symptoms for further organ injuries.The chemical was detected in the blood of all patients and caused multiple organ injuries,predominantly liver injury,including kidney,myocardium,and micro-circulation.Three patients recovered smoothly after comprehensive treatments,including artificial liver therapy,continuous renal replacement therapy,glucocorticoids,and other symptomatic and supportive treatments.One patient survived by liver transplantation.The postoperative pathological findings of the removed liver showed acute liver failure,and immunofluorescence staining confirmed the abundance of mitophagy in residual hepatocytes.Conclusions:This study is the first to elaborate the clinical characteristics of patients with 2-amino-5-chloro-N,3-dimethylbenzamide poisoning.The chemical enters the body through the respiratory tract and skin during industrial production.The 2-amino-5-chloro-N,3-dimethylbenzamide poisoning causes multiple-organ dysfunction with a predominance of liver injury.Liver transplantation may be an effective option for patients with severe liver failure.The mechanisms of liver injury induced by 2-amino-5-chloro-N,3-dimethylbenzamide might involve abnormal mitochondrial function and mitophagy. 展开更多
关键词 2-amino-5-chloro-N 3-dimethylbenzamide Poisoning Clinical characteristics Liver injury
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Extractant(2,3-dimethylbutyl)(2,4,40-trimethylpentyl) phosphinic acid(INET-3) impregnated onto XAD-16 and its extraction and separation performance for heavy rare earths from chloride media 被引量:6
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作者 Junlian Wang Meiying Xie +2 位作者 Juanjuan Ma Huajun Wang Shengming Xu 《Journal of Rare Earths》 SCIE EI CAS CSCD 2017年第12期1239-1247,共9页
(2,3-Dimethylbutyl)(2,4,40-trimethylpentyl)phosphinic acid(INET-3) was impregnated onto dry macroporous resins XAD-16 and pretreated XAD-16 with ethyl alcohol and HCl(Pre-XAD-16) to prepare the solvent impregn... (2,3-Dimethylbutyl)(2,4,40-trimethylpentyl)phosphinic acid(INET-3) was impregnated onto dry macroporous resins XAD-16 and pretreated XAD-16 with ethyl alcohol and HCl(Pre-XAD-16) to prepare the solvent impregnated resins SIRs-INET-3/XAD-16 and SIRs-INET-3/Pre-XAD-16. The molecular weight distribution of the low molecular weight(LMW) polymers washed off by ethyl alcohol during XAD-16 pretreatment was determined by gel permeation chromatography(GPC). The macroporous resins(XAD-16 & Pre-XAD-16), the corresponding solvent impregnated resins(SIRs-INET-3/XAD-16 &SIRs-INET-3/Pre-XAD-16) and the PVA coated SIRs-INET-3/Pre-XAD-16 with boric acid as cross-linking agent were characterized by FT-IR, SEM-EDS and TGA. The effects of XAD-16 pretreatment and PVA coating technology on RE(III) adsorption equilibrium time, INET-3 losses during extraction and adsorption capacity were investigated. The adsorption kinetics, selectivity and stripping behaviors of SIRs-INET-3/XAD-16 were further studied. The washed off LMW polymers had the Mn of 36,656, Mw of 40,310 and polydispersity coefficient of 1.10. The SIRs-INET-3/XAD-16 had shorter equilibrium time,less INET-3 loss and more Tm(III) adsorption capacity than the SIRs-INET-3/Pre-XAD-16. The PVA coated SIRs-INET-3/Pre-XAD-16 had less INET-3 loss and more Tm(III) adsorption capacity but longer equilibrium time than the uncoated SIRs-INET-3/Pre-XAD-16. The adsorption of RE(III) on the SIRsINET-3/XAD-16 followed the pseudo-second-order kinetic model. The Tm(III) accumulative adsorption amounts onto SIRs-INET-3/XAD-16 after eight extraction stages was 23.6 mg/g. The separation factors of adjacent heavy RE(III) β(Er/Ho), β(Tm/Er), β(Yb/Tm) and β(Lu/Yb) values were 1.76, 2.59, 2.56 and 1.19,respectively. The adsorbed Lu(III) onto the SIRs-INET-3/XAD-16 can be stripped completely by 1.0 mol/L H2SO4. 展开更多
关键词 (2 3-dimethylbutyl)(2 4 4'-trimethylpentyl) phosphinic acid Solvent impregnated resins Adsorption Heavy rare earths
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Vapor Pressure Measurement of Water+1,3-Dimethylimidazolium Tetrafluoroborate System
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作者 武向红 李静 +2 位作者 范丽华 郑丹星 董丽 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2011年第3期473-477,共5页
In absorption cycles,ionic liquid(IL)1,3-dimethylimidazolium tetrafluoroborate([Dmim]BF4)may be a promising absorbent of working pair using water as refrigerant.The vapor pressures of[Dmim]BF4 aqueous solution were me... In absorption cycles,ionic liquid(IL)1,3-dimethylimidazolium tetrafluoroborate([Dmim]BF4)may be a promising absorbent of working pair using water as refrigerant.The vapor pressures of[Dmim]BF4 aqueous solution were measured with the boiling-point method in the temperature range from 312.25 to 403.60 K and in the mass concentration range of 65%to 90%of[Dmim]BF4.The experimental data were correlated with an Antoine-type equation and the Non-Random Two-Liquid(NRTL)model,and the average absolute deviations between the experimental and calculated values were 1.06%and 1.15%,respectively.For the[Dmim]BF4 aqueous solution,the experimental vapor pressures show negative deviations from the calculated data with Raoult's law.For higher mass concentration of the IL,the deviation is more negative.In addition,the vapor pressures,the hydrophilicity and the solubility of[Dmim]BF4 aqueous solutions were compared with those of[Dmim]Cl aqueous solutions and [Bmim]BF4 aqueous solutions at IL-mole fraction of 0.20. 展开更多
关键词 ionic liquid 1 3-dimethylimidazolium tetrafluoroborate vapor pressure absorption cycle working pair
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Adsorption of BSA on Carbon-coated Fe_3O_4 Microspheres Activated with 1-ethyl-3-(3-dimethylaminopropyl)-Carbodiimide Hydrochloride 被引量:2
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作者 单嘉敏 KIM Cholhwan +2 位作者 ZHANG Zefei 王林山 SUN Ting 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2018年第1期1-8,共8页
Carbon-coated Fe3O4( Fe3O4/C) microspheres activated with 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide hydrochloride(EDC) were prepared, characterized and applied to adsorb bovine serum albumin(BSA). The pre... Carbon-coated Fe3O4( Fe3O4/C) microspheres activated with 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide hydrochloride(EDC) were prepared, characterized and applied to adsorb bovine serum albumin(BSA). The prepared magnetic microspheres had spherical core-shell structure with a uniform and continuous carbon coating coupled with activation by EDC, and possessed superparamagnetic characteristics. The experimental results showed that the adsorption amount of BSA on the EDC-activated Fe3O4/C(Fe3O4/C-EDC) microspheres was higher than that on the Fe3O4/C microspheres. The maximum adsorption of BSA on Fe3O4/C-EDC microspheres occurred at pH 4.7, which was the isoelectric point of BSA. At low concentrations(below 1.0 M), salt had no noticeable effect on BSA adsorption. The BSA adsorption of Fe3O4/C-EDC microspheres had a better fit to the Langmuir model than the Freundlich isotherm and Temkin isotherm model, and the kinetic data were well described by the pseudo-second-order model. The adsorption equilibrium could be reached within 20 min. High desorption efficiency(97.6%) of BSA from Fe3O4/C-EDC microspheres was obtained with 0.5 M Na2HPO4(pH 9.4) as the desorbent. 展开更多
关键词 Fe3O4/C microspheres EDC ADSORPTION BSA
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Synthesis and Crystal Structure of 7-Amino-2,3,4,5-tetrahydro-1,3-dimethyl-5-(2-nitrophenyl)-2,4-dioxo-1H-pyrano[2,3-d]pyrimidine-6-carbonitrile DMF Solvate
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作者 梁静 张梅梅 王香善 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第3期301-305,共5页
The title compound 7-amino-2,3,4,5-tetrahydro-1,3-dimethyl-5-(2-nitrophenyl)- 2,4- dioxo-1H-pyrano[2,3-d] pyrirnidine-6-carbonitrile DMF solvate 1 (C19H20N6O6, Mr = 428.41) was synthesized and crystallized. The cr... The title compound 7-amino-2,3,4,5-tetrahydro-1,3-dimethyl-5-(2-nitrophenyl)- 2,4- dioxo-1H-pyrano[2,3-d] pyrirnidine-6-carbonitrile DMF solvate 1 (C19H20N6O6, Mr = 428.41) was synthesized and crystallized. The crystal belongs to the monoclinic system, space group P2 1/c with a = 11.383(2), b = 13.372(2), c = 13.673(2)A, β = 97.380(4)°, Z = 4, V = 2063.8(6)A^3, Dc = 1.379 g/cm^3,μ(MoKα) = 0.105 mm^-1, F(000) = 896, the final R = 0.0738 and wR = 0.1647 for 2964 observed reflections (I〉 2σ(I)). X-ray analysis reveals that the new pyran ring is coplanar, which is obviously different from those of other similar compounds. In addition, the unclassical hydrogen bonds of C-H…O and C-H…N are presented in the crystals except for the normal hydrogen bonds of N-H…O. 展开更多
关键词 crystal structure pyrano[2 3-d] pyrimidine synthesis
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Solid-Liquid Equilibria of Musk Ketone, Musk Xylene and 1,3-Dimethyl-2,4-Dinitro-5-Tert-Butyl Benzene 被引量:1
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作者 曲红梅 白鹏 +1 位作者 杨志才 余国琮 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2004年第2期294-296,共3页
The solid-liquid equilibria of musk ketone + musk xylene, musk xylene +l,3-dimethyl-2,4-dinitro-5-tert-butyl benzene are measured by differential scanning calorimeter (DSC), these systems are proved to be simple eutec... The solid-liquid equilibria of musk ketone + musk xylene, musk xylene +l,3-dimethyl-2,4-dinitro-5-tert-butyl benzene are measured by differential scanning calorimeter (DSC), these systems are proved to be simple eutectics. Moreover the melting points and the fusion enthalpies of musk ketone, musk xylene and 1,3-dimethyl-2,4-dinitro-5-tert-butyl benzene are also measured by the DSC. These solid-liquid equilibrium data and the heats of fusion are reported for the first time. Then UNIFAC model is used to correlate the sofid-liquid equilibrium data. It is shown that the solid-liquid equilibria of musk systems can be predicted by the UNIFAC model. 展开更多
关键词 solid-liquid equilibria differential scanning calorimeter musk ketone musk xylene 1 3-dimethy1-2 4-dinitro-5-tert-butyl benzene
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Research on Synthesis of 4,5-Dihydroxy-1,3-Dimethyl-2-Imidazo-lidinone
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作者 沈勇 孙铠 《Journal of China Textile University(English Edition)》 EI CAS 1998年第2期32-34,共3页
The formaidehyde-free finishing agent 4,5-di-hydroxy-1,3-dimethy1-2-imidazolidinone(DMeDHEU)was prepared by the reaction of 1,3-dimethylurea and glyoxal.The reaction rate and equilib-rium conversion in relation to pH ... The formaidehyde-free finishing agent 4,5-di-hydroxy-1,3-dimethy1-2-imidazolidinone(DMeDHEU)was prepared by the reaction of 1,3-dimethylurea and glyoxal.The reaction rate and equilib-rium conversion in relation to pH value,molar ratio,temperature and catalyst were studied.The conversionto DMeDHEU,catalyzed with citric acid/anhydrousNaAc,reached 95% in 6 hours at 40℃, pH 5.5 andmolar ratio 1.2. 展开更多
关键词 formaldehyde - free finishing agent 4 5 - di-hydroxy -1 3- DIMETHYL - 2 - IMIDAZOLIDINONE (DMeD-HEU) synthesis reaction rate conversion ratio.
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Structural Dynamics of 3-Dimethylamino-2-methyl-propenal in S2(ππ^*) State
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作者 潘胜 薛佳丹 郑旭明 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2014年第2期149-158,I0003,共11页
The photophysics of 3-dimethylamino-2-methyl-propenal (DMAMP) after excitation to the S2 (ππ^*) electronic state was studied using the resonance Raman spectroscopy and complete active space self-consistent fiel... The photophysics of 3-dimethylamino-2-methyl-propenal (DMAMP) after excitation to the S2 (ππ^*) electronic state was studied using the resonance Raman spectroscopy and complete active space self-consistent field method calculations. The transition barriers of the ground state tautomerization reactions between DMAMP and its three isomers were determined at B3LYP/6-311++G(d,p) level of theory. The vibrational spectra were assigned. The A- band resonance Raman spectra were obtained in acetonitrile with excitation wavelengths in resonance with the first intense absorption band to probe the structural dynamics of DMAMP. The B3LYP-TD computation was carried out to determine the relative A-band resonance Raman intensities of the fundamental modes, and the result indicated that the vibronic-coupling existed in Franck-Condon region. Complete active space self-consistent field (CASSCF) calculations were carried out to determine the excitation energies of the lower-lying singlet and triplet excited states, the conical intersection points and the intersystem crossing points. The A-band short-time structural dynamics and the corresponding decay dynamics of DMAMP were obtained by analysis of the resonance Raman intensity pattern and CASSCF computations. It was found that a sudden de-conjugation between C1=O6 and C2=C3 occurred at the Franck-Condon region of the S2(ππ^*) state, while the enhancement of the conjugation interaction between C3 and N(CH3)2, and between C1 and C2 evolutions shortly after the wavepacket leaves away the Pranck-Condon region via the excited state charge redistribution. The de-conjugation interaction between C1=O6 and C2=C3 made the rotation of C3=N(CH3)2 group around the C2-C3 bond much easier, while the enhanced conjugation between C1 and C2, and between C3 and N(CH3)2 made the rotation around the C1-C2 bond and C3-N5 more difficult. It was revealed that the initial structural dynamics of DMAMP was predominantly towards the CI-I(S2/S0) point, while the opportunities towards either CI-2(S2/S0) or CI-3(S2/S0) point were negligible. Two decay channels of DMAMP from S2,FC(ππ^*) to So or Tl,min via various CIs and ISCs were proposed. 展开更多
关键词 Structural dynamics Conical intersection Excited state Resonance Raman CASSCF calculation
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仿木年轮结构Si_(3)N_(4)/Ni和316配副在海洋环境中的摩擦磨损性能研究
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作者 陈威 王朝 +4 位作者 周奥 李耶童 赵文卓 张建军 杨勇强 《陕西科技大学学报》 北大核心 2026年第1期152-160,共9页
本论文系统研究了仿木年轮Si_(3)N_(4)/Ni复合材料在海水中的摩擦磨损性能.在本研究中,利用热压烧结工艺制备仿木年轮的Si_(3)N_(4)/Ni复合材料,采用端面磨损试验机研究Si_(3)N_(4)/Ni复合材料与316不锈钢配副在人工海水环境中的摩擦磨... 本论文系统研究了仿木年轮Si_(3)N_(4)/Ni复合材料在海水中的摩擦磨损性能.在本研究中,利用热压烧结工艺制备仿木年轮的Si_(3)N_(4)/Ni复合材料,采用端面磨损试验机研究Si_(3)N_(4)/Ni复合材料与316不锈钢配副在人工海水环境中的摩擦磨损性能,利用扫描电子显微镜(SEM)观察与分析摩擦副表面的磨损形貌,采用EDS能谱仪和拉曼光谱来定性分析磨损面的表面元素与物质分布.结果表明,随着滑动速度增大,纯氮化硅和Si_(3)N_(4)/Ni复合材料与316不锈钢配副的摩擦系数均有所增大,在相同速度下,Si_(3)N_(4)/Ni复合材料与316配副表现出较好的摩擦磨损性能.当滑动速度为100 r/min时,Si_(3)N_(4)/Ni-316摩擦副表现出最优的摩擦学性能,摩擦系数为0.45,复合材料销磨损率为1.503×10^(-6)mm^(3)/Nm,金属盘磨损率为1.03×10^(-4)mm^(3)/Nm.Si_(3)N_(4)/Ni复合材料表现出相对较好的摩擦学性能,这主要归因于在复合材料摩擦表面发生了摩擦化学反应,生成硅胶(SiO_(2))和Ni_(2)SiO_(4)等物质,起到了减摩与润滑作用. 展开更多
关键词 Si_(3)N_(4)复合陶瓷 海水环境 摩擦磨损
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基于无电离层组合的BDS-3/Galileo多频单点定位模型及性能评估
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作者 陈健 董彪 +1 位作者 赵兴旺 刘超 《大地测量与地球动力学》 北大核心 2026年第1期17-25,共9页
BDS-3和Galileo均可以提供5频信号服务。为充分利用多频信号数据,建立基于无电离层组合的BDS-3/Galileo多频单点定位模型,确定多频无电离层组合系数;选取48个多模GNSS实验(multi-GNSS experiment,MGEX)跟踪网测站数据,系统评估基于无电... BDS-3和Galileo均可以提供5频信号服务。为充分利用多频信号数据,建立基于无电离层组合的BDS-3/Galileo多频单点定位模型,确定多频无电离层组合系数;选取48个多模GNSS实验(multi-GNSS experiment,MGEX)跟踪网测站数据,系统评估基于无电离层组合的多频伪距单点定位(SPP)性能。实验结果表明,多频组合观测值有助于提升BDS-3、Galileo及BDS-3/Galileo系统SPP定位精度,相较于3频SPP定位,4频、5频SPP定位精度均有不同程度提升。其中多频组合对BDS-3系统提升最为明显,在E、N、U方向上,BDS-3三频SPP定位RMS均值分别为0.56 m、0.59 m、1.46 m,而4频和5频RMS均值相近,分别为0.53 m、0.55 m、1.40 m和0.52 m、0.55 m、1.38 m。相比BDS-3、Galileo单系统,BDS-3/Galileo组合系统5频SPP定位精度分别提高30.8%、29.1%、25.4%和28.0%、30.4%、25.9%。 展开更多
关键词 BDS-3/Galileo 多频观测值 无电离层组合 单点定位 定位性能
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2型糖尿病患者血清TIMP3、Trx-1表达及其与肠道菌群的关系
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作者 陈袁 赵倩 徐台林 《中国病原生物学杂志》 北大核心 2026年第1期50-54,共5页
目的检测2型糖尿病(T2DM)患者血清基质金属蛋白酶抑制因子3(TIMP3)、硫氧还蛋白1(Trx1)表达水平,分析血清TIMP3、Trx-1与肠道菌群的关系。方法选取2023年8月至2025年2月至本院就诊的100例T2DM患者为试验组,另选取同期至院体检健康者100... 目的检测2型糖尿病(T2DM)患者血清基质金属蛋白酶抑制因子3(TIMP3)、硫氧还蛋白1(Trx1)表达水平,分析血清TIMP3、Trx-1与肠道菌群的关系。方法选取2023年8月至2025年2月至本院就诊的100例T2DM患者为试验组,另选取同期至院体检健康者100例为对照组。收集2组临床资料,ELISA法检测2组血清TIMP3、Trx-1水平,鉴定并计算2组肠道菌群类别和水平。采用Pearson分析血清TIMP3、Trx-1与其他临床资料和肠道菌水平的相关性;采用Logistic回归分析T2DM的影响因素。结果试验组空腹血糖(FPG)(7.82±1.03 mmol/L)、胰岛素抵抗指数(HOMA-IR)(5.77±0.82)水平高于对照组(5.36±0.88 mmol/L、2.39±0.45),血清TIMP3(756.58±140.49 pg/mL)、Trx-1(13.05±2.82 ng/mL)水平低于对照组(943.25±153.22 pg/mL、16.77±3.49 ng/mL)(P<0.05)。试验组双歧杆菌(59.00%、4.38±0.74 CFU/g)、阿克曼氏菌(43.00%、4.61±0.62 CFU/g)、乳杆菌(62.00%、3.35±0.68 CFU/g)、拟杆菌(39.00%、5.13±0.92 CFU/g)阳性率及其水平均低于对照组[(86.00%、5.63±0.82 CFU/g)、(71.00%、5.57±0.76 CFU/g)、(79.00%、3.99±0.74 CFU/g)、(76.00%、7.22±1.15 CFU/g)],梭杆菌(48.00%、2.46±0.47 CFU/g)、肠球菌(66.00%、4.28±0.67 CFU/g)阳性率及其水平均高于对照组[(26.00%、2.08±0.42 CFU/g)、(35.00%、3.61±0.53 CFU/g)](P<0.05)。血清TIMP3、Trx-1与FPG(r=-0.482、-0.473)、HOMA-IR(r=-0.488、-0.476)、梭杆菌(r=-0.442、-0.431)、肠球菌(r=-0.457、-0.458)水平呈负相关,与双歧杆菌(r=0.475、0.472)、阿克曼氏菌(r=0.463、0.459)、乳杆菌(r=0.445、0.438)、拟杆菌(r=0.481、0.476)呈正相关(P<0.05)。FPG[OR(95%CI)=4.992(2.124~11.733)]、HOMA-IR[OR(95%CI)=5.103(2.133~12.207)]、梭杆菌[OR(95%CI)=3.016(1.669~5.451)]、肠球菌[OR(95%CI)=3.227(1.744~5.971)]水平升高,TIMP3[OR(95%CI)=0.282(0.193~0.412)]、Trx-1[OR(95%CI)=0.265(0.187~0.375)]、双歧杆菌[OR(95%CI)=0.388(0.255~0.591)]、阿克曼氏菌[OR(95%CI)=0.425(0.269~0.671)]、乳杆菌[OR(95%CI)=0.304(0.171~0.542)]、拟杆菌[OR(95%CI)=0.349(0.246~0.496)]水平降低是影响T2DM的危险因素(P<0.05)。结论T2DM患者血清TIMP3、Trx-1水平均下降,患者的肠道菌群紊乱,其中双歧杆菌、阿克曼氏菌、乳杆菌、拟杆菌水平降低,梭杆菌、肠球菌水平升高,且肠道菌群变化与血清TIMP3、Trx-1水平有关。 展开更多
关键词 2型糖尿病 肠道菌群 基质金属蛋白酶抑制因子3 硫氧还蛋白1 关系
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ω-3多不饱和脂肪酸对重症急性胰腺炎继发腹腔感染患者炎症反应、免疫功能及营养指标的影响
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作者 张侃 詹磊磊 程树红 《西北药学杂志》 2026年第1期186-191,共6页
目的观察ω-3多不饱和脂肪酸对重症急性胰腺炎(severe acute pancreatitis,SAP)继发腹腔感染患者炎症反应、免疫功能及营养指标的影响。方法选取2022年4月—2024年2月收治的SAP继发腹腔感染患者102例作为研究对象,采用抽签法分为2组,每... 目的观察ω-3多不饱和脂肪酸对重症急性胰腺炎(severe acute pancreatitis,SAP)继发腹腔感染患者炎症反应、免疫功能及营养指标的影响。方法选取2022年4月—2024年2月收治的SAP继发腹腔感染患者102例作为研究对象,采用抽签法分为2组,每组51例。常规组给予鼻胃管减压、补液、抗休克、抗感染和解痉等常规治疗,营养组在常规组治疗的基础上给予ω-3多不饱和脂肪酸治疗。观察2组的病原菌分布情况,比较2组的单核细胞趋化因子蛋白1(monocyte chemoattractant protein-1,MCP-1)、肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)、白细胞计数(white blood cell count,WBC)、生长激素释放肽(ghrelin)、免疫功能、营养代谢指标及急性生理和慢性健康评估Ⅱ(Acute Physiology and Chronic Health Evaluation-Ⅱ,APACHEⅡ)评分、Balthazar CT评分。结果2组病原菌鉴定结果均以革兰氏阴性菌为主,其次为革兰氏阳性菌和真菌。2组病原菌鉴定分布情况比较差异无统计学意义(P>0.05)。治疗后,2组的前白蛋白(prealbumin,PA)、白蛋白(albumin,ALB)、血红蛋白(hemoglobin,Hb)均升高,且营养组均高于常规组(P<0.05)。治疗后,2组的MCP-1、ghrelin、TNF-α、WBC均降低,且营养组均低于常规组(P<0.05);2组的CD3^(+)、CD4^(+)、CD4^(+)/CD8^(+)均升高,且营养组均高于常规组(P<0.05);2组的APACHEⅡ、Balthazar CT评分均降低,且营养组均低于常规组(P<0.05)。结论ω-3多不饱和脂肪酸可减轻SAP继发腹腔感染患者的病情程度,减轻炎症反应,提高营养指标和免疫功能。 展开更多
关键词 Ω-3多不饱和脂肪酸 重症急性胰腺炎 腹腔感染 免疫功能 炎症反应 病原菌
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宫颈癌患者血清TAP、TSGF、TFF3水平及与肿瘤侵袭、凋亡的关系分析
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作者 张娟 孟祥楠 王锋 《国际检验医学杂志》 2026年第1期72-77,共6页
目的探究宫颈癌患者血清肿瘤异常蛋白(TAP)、恶性肿瘤生长因子(TSGF)、三叶因子3(TFF3)水平及与肿瘤侵袭、凋亡的关系。方法选取2021年1月至2022年12月该院收治的76例宫颈癌患者作为癌症组,另选取同期76例宫颈癌前病变患者作为癌前病变... 目的探究宫颈癌患者血清肿瘤异常蛋白(TAP)、恶性肿瘤生长因子(TSGF)、三叶因子3(TFF3)水平及与肿瘤侵袭、凋亡的关系。方法选取2021年1月至2022年12月该院收治的76例宫颈癌患者作为癌症组,另选取同期76例宫颈癌前病变患者作为癌前病变组。比较血清指标[TAP、TSGF、TFF3、肿瘤抗原-4(TA4)]水平,采用受试者工作特征(ROC)曲线分析血清TAP、TSGF、TFF3水平对宫颈癌的诊断价值。比较两组肿瘤侵袭、凋亡相关基因[基质金属蛋白酶-9(MMP-9)、含半胱氨酸的天冬氨酸蛋白水解酶-3(Caspase-3)、B淋巴细胞瘤-2(bcl-2)基因]表达;分析宫颈癌患者血清指标与肿瘤侵袭、凋亡相关基因、临床病理特征之间的关系。结果协方差分析校正年龄、性别后,Ⅲ期宫颈癌患者TAP、TSGF和TFF3水平高于Ⅱ期和Ⅰ期宫颈癌患者(P<0.05),肿瘤低分化、有淋巴结转移的宫颈癌患者TAP、TSGF和TFF3水平高于肿瘤高分化和无淋巴结转移宫颈癌患者(P<0.05)。癌症组血清TAP、TSGF、TFF3和TA4水平均高于癌前病变组(P<0.05)。Pearson相关性分析结果显示,血清TAP、TSGF、TFF3水平分别与TA4水平呈正相关(P<0.05)。ROC曲线分析结果显示,血清TAP、TSGF、TFF3水平联合诊断宫颈癌的曲线下面积较大,具有良好的诊断价值。癌症组癌组织中Caspase-3基因表达水平低于癌前病变组(P<0.05),MMP-9和bcl-2基因表达水平均高于癌前病变组(P<0.05)。Pearson相关性分析结果显示,血清TAP、TSGF、TFF3水平分别与癌组织Caspase-3基因表达水平呈负相关(P<0.05),与MMP-9、bcl-2基因表达水平呈正相关(P<0.05)。结论宫颈癌患者血清TAP、TSGF、TFF3水平异常升高,且其水平变化可能与肿瘤侵袭、凋亡有关。 展开更多
关键词 宫颈癌 肿瘤异常蛋白 恶性肿瘤生长因子 三叶因子3 侵袭 凋亡
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白细胞介素-35基因多态性与感染性疾病的关系
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作者 谭婧(综述) 向瑜(审校) 《检验医学与临床》 2026年第1期127-132,共6页
白细胞介素(IL)-35是新发现的细胞因子,作为IL-12家族成员之一,由Epstein-Barr病毒诱导的基因3亚基及IL-12A亚基构成,在抗炎、调节T细胞功能、免疫抑制和维持免疫耐受中发挥重要作用。有研究发现IL-35在多种感染性疾病中表达异常,IL-35... 白细胞介素(IL)-35是新发现的细胞因子,作为IL-12家族成员之一,由Epstein-Barr病毒诱导的基因3亚基及IL-12A亚基构成,在抗炎、调节T细胞功能、免疫抑制和维持免疫耐受中发挥重要作用。有研究发现IL-35在多种感染性疾病中表达异常,IL-35的单核苷酸多态性可通过影响IL-35水平,在感染性疾病的易感性、病程进展及预后中发挥作用。特定的单核苷酸多态性位点可能改变IL-35的表达或功能,从而影响个体对病毒、细菌等病原体的免疫应答。该文就近年来IL-35的基因多态性与新型冠状病毒感染、乙型病毒性肝炎、丙型病毒性肝炎、肺结核等感染性疾病相关性的研究进行综述,探讨IL-35在疾病发生和发展中的作用,为感染性疾病的临床治疗提供理论依据和潜在靶点。 展开更多
关键词 白细胞介素-35 Epstein-Barr病毒诱导的基因3 白细胞介素-12A 基因多态性 感染性疾病
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