3－C8-10烷氧基丙腈催化加氢制3－C8-10烷氧基丙胺

以3－C8-10烷氧基丙腈为原料,骨架镍为催化剂,制备了3－C8-10烷氧基丙胺。同时探讨了反应温度、反应时间、H2压力、NH3压力、骨架镍用量、H2O用量等因素对加氢反应的影响,确定了优化的工艺条件：在130℃、H2压力2．0MPa、NH3压力1．0MPa、骨架镍用量2．0％和H2O用量2．0％（相对于3－C8-10烷氧基丙腈的质量）下反应3h,在此条件下,产品收率为93．56％。     

脂肪醇脱水制C8、C8/C10α-烯烃的研究

采用催化剂催化脂肪醇脱水制成了C8-C10α-烯烃,通过改进催化剂和开发先进工艺,在脱水装置上进行脂肪醇脱水实验,得出较为理想的烯烃产品。产品经过了气相色谱法分析和蒸馏分离。实验结果表明,Ba、H/γ-Al2O3为较好的催化剂,并得出Ba负载量为12%、催化剂焙烧温度550℃、装置反应温度310℃、空速0.3h^-1时的C8、C8/C10烯烃选择性均达到最大值98.1%和97.5%。     

Ferromagnetism and optical properties of La1???x Al x FeO3 nanopowders

La_{1 − x} Al _x FeO₃ (x = 0.0, 0.05, 0.1, 0.2, 0.3, 0.4, and 0.5) nanopowders were prepared by polymerization complex method. All prepared samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), and UV-vis spectrophotometry (UV-vis). The magnetic properties were investigated using a vibrating sample magnetometer (VSM). The X-ray results of all samples show the formation of an orthorhombic phase with the second phase of α-Fe₂O₃ in doped samples. The crystallite sizes of nanoparticles decreased with increasing Al content, and they are found to be in the range of 58.45 ± 5.90 to 15.58 ± 4.64 nm. SEM and TEM images show the agglomeration of nanoparticles with average particle size in the range of 60 to 75 nm. The FT-IR spectra confirm the presence of metal oxygen bonds of O-Fe-O and Fe-O in the FeO₆ octahedra. The UV-vis spectra show strong absorption peaks at approximately 285 nm, and the calculated optical band gaps are found to be in the range of 2.05 to 2.09 eV with increasing Al content. The M-H loop of the pure sample is antiferromagnetic, whereas those of the doped samples tend to be ferromagnetic with increasing Al content. The magnetization, remanent magnetization, and coercive field of the Al-doped sample with x = 0.5 are enhanced to 1.665 emu/g, 0.623 emu/g, and 4,087.0 Oe, respectively.     

Synthesis,microstructure, and magnetic properties of monosized Mn x Zn y Fe3 ? x ? y O4 ferrite nanocrystals

We report the synthesis and characterization of ferrite nanocrystals which exhibit high crystallinity and narrow size distributions. The three types of samples including Zn ferrite, Mn ferrite, and Mn-Zn ferrite were prepared via a non-aqueous nanoemulsion method. The structural, chemical, and magnetic properties of the nanocrystals are analyzed by transmission electron microscopy, X-ray diffraction, X-ray fluorescence, and physical property measurement system. The characterization indicates that the three types of ferrite nanocrystals were successfully produced, which show well-behaved magnetic properties, ferrimagnetism at 5 K and superparamagnetism at 300 K, respectively. In addition, the magnetization value of the ferrites increases with the increasing concentration of Mn.     

新一代杀菌剂双C8—10烷基二甲基氯化铵

本文介绍了国外季铵盐杀菌剂的研究开发进展情况,对几代季铵盐杀菌剂的性能进行了比较。第三代产品杀菌性能良好,而由它与第一代产品复配得到的第四代产品,具有特别优异的性能;同时简介了国内该产品的发展情况。     

杀菌剂双C8—10烷基二甲基氯化铵的合成

介绍了用于杀菌剂双Ｃ８－１０烷基二甲基氯化铵合成的Ｃｕ－Ｎｉ／载体催化剂及在适宜瓜条件下所得的反应结果。     

非离子表面活性剂C8—C10脂肪酸甘油酯的合成及应用

本研究是利用制皂过程中分离出的副产物Ｃ８－Ｃ１０混合脂肪酸与甘油酯化后进行氧乙烯化反应，合成一种新型的非离子表面活性剂，并作为纺织助应用于涤纶织物的后整理工艺，提高了织物的吸水性，抗静电性和易去污等性能。     

Effects of 1600 °C annealing atmosphere on the microstructures and mechanical properties of C/SiC composites fabricated by precursor infiltration and pyrolysis

Effects of 1600 °C annealing atmosphere on microstructures and mechanical properties of the C/SiC composites fabricated by PIP route were remarkable. Due to carbothermic reductions, the ratios of weight loss of the C/SiC composites were all above 7 wt% in 1 h. Consequently, the mechanical properties all had a significant drop during the first hour of annealing because of the bonding between the fibers and matrix remarkably weaken by cracks and pores. And then the flexural strengths gradually decreased with the annealing time increasing, when the flexural moduli slightly changed within the range of 44.2–49.7 GPa. However, the fracture behaviors of the C/SiC composites annealed under Ar faster became brittle than the C/SiC composites annealed under vacuum. The C/SiC composites annealed under Ar for 5 h and under vacuum for 10 h both became brittle mainly due to the sensitive to annealing of the weak carbon interphase, while the C/SiC composites annealed under Ar for 7 h became brittle mainly due to the chemical bonding between the fibers and matrix. And these phenomena were confirmed by the post densification and the stress-releasing annealing.     

C10叔碳酸

C_(10)叔碳酸是一类重要的化工原料,它们的衍生物在工业上具有广泛的应用。该产品用于生产聚合物、药物、农药、农用化学品、化妆品和金属加工业。西南化工研究院于1995年开始C_(10)叔碳酸的合成研究,已建成200t/a的生产装置,目前正在筹建千吨级的工业装置。     

Preparation and Characterization of C10–C14 Alkyl Cellulose Ester Sulfate Surfactant

The aim of this work is to synthesize surfactants based on cellulose with different molecular weights. Raw cotton cellulose was tailored into cellulose segments with different molecular weights by a hydrothermal process, then the average degree of polymerization (DP) was determined by viscosimetry and the molecular weight distribution was estimated by gel permeation chromatography. The C₁₀–C₁₄ alkyl cellulose ester sulfate surfactants were prepared by hydrophilic sulfonation and hydrophobic esterification. The surface tension of the surfactants solution was obtained by the Wilhelmy plate method. Results showed that the cellulose segments presented a broader distribution compared with the raw material. The critical micelle concentration (CMC) value decreased from 1.08 to 0.86 wt% as the hydrophobic chain length was increased from 10 to 14. The CMC values of cellulose surfactants with C₁₄-acyl chloride hydrophobization decreased from 1.32 to 0.86 wt% as the DP was decreased from 2,700 to 296.     

New Trends and Future Opportunities in the Enzymatic Formation of C−C,C−N,and C−O bonds

Organic chemistry provides society with fundamental products we use daily. Concerns about the impact that the chemical industry has over the environment is propelling major changes in the way we manufacture chemicals. Biocatalysis offers an alternative to other synthetic approaches as it employs enzymes, Nature's catalysts, to carry out chemical transformations. Enzymes are biodegradable, come from renewable sources, operate under mild reaction conditions, and display high selectivities in the processes they catalyse. As a highly multidisciplinary field, biocatalysis benefits from advances in different areas, and developments in the fields of molecular biology, bioinformatics, and chemical engineering have accelerated the extension of the range of available transformations (E. L. Bell et al., Nat. Rev. Meth. Prim. 2021 , 1, 1–21). Recently, we surveyed advances in the expansion of the scope of biocatalysis via enzyme discovery and protein engineering (J. R. Marshall et al., Tetrahedron 2021 , 82, 131926). Herein, we focus on novel enzymes currently available to the broad synthetic community for the construction of new C−C, C−N and C−O bonds, with the purpose of providing the non-specialist with new and alternative tools for chiral and sustainable chemical synthesis.     

加合物C10H11NO8的合成及晶体结构研究

主要介绍了有机加合物C10 H11 NO(8)的合成及结构研究.采用缓慢蒸发溶剂法合成了有机加合物单晶体,该加合物通过红外、热化学和X-射线单晶衍射分析方法确证.X-射线单晶衍射分析显示,晶体中分子主要依靠分子间氢键相互连接,在晶体中构成了氢键网络.对该加合物分子的微观晶体结构进行了讨论.     

Analysis of Different Ploidy and Parent–Offspring Genomic DNA Methylation in the Loach Misgurnus anguillicaudatus

In this study, we selected natural polyploidy loach (diploid, triploid and tetraploid) and hybrid F₁ generation obverse cross (4 × 2) and inverse cross (2 × 4) by diploids and tetraploids as the research model. The MSAP (methylation-sensitive amplified polymorphism) reaction system was established by our laboratory to explore methylation levels and pattern diversification features at the whole genome level of the polyploidy loach. The results showed that the total methylation and full methylation rates decreased on increased ploidy individuals; moreover, the hemimethylation rate showed no consistent pattern. Compared with diploid loach, the methylation patterns of tetraploid sites changed 68.17%, and the methylation patterns of triploid sites changed 73.05%. The proportion of hypermethylation genes is significantly higher than the proportion of demethylation genes. The methylation level of reciprocal cross F₁ generation is lower than the male diploid and higher than the female tetraploid. The hemimethylation and total methylation rate of the cross hybrid F₁ generation is significantly higher than the orthogonal F₁ generation (p < 0.01). After readjusting, the methylation pattern of genome DNA of reciprocal hybrids changed 69.59% and 72.83%, respectively.     

Density and N2O solubility of sodium and potassium carbonate solutions in the temperature range 25 to 80 °C

To deduce kinetic parameters for the reactions of carbon dioxide (CO₂) in carbonate solutions the physical solubility of CO₂ into the reacting solution is needed. To measure the physical solubility directly with CO₂ is not possible, so the solubility of nitrous oxide (N₂O) is normally measured instead. The physical solubility of CO₂ can then be calculated based on the solubility of CO₂ and N₂O into water and the solubility of N₂O in the solution of interest invoking the so called N₂O analogy (Clarke, 1964; Laddha et al., 1981). To obtain good accuracy of the solubility measurements the accurate density of the solution is needed. In this study the densities were measured with pycnometers up to 353 K.In this paper the parameters in the model of Weisenberger and Schumpe (1996) were refitted specifically for the two carbonate systems using experimental data up to 353 K and up to 30 wt% (3.7 kmol/m³) aqueous sodium carbonate and up to 50 wt% (5.5 kmol/m³) aqueous potassium carbonate solutions.     

Analysis of the Parameters of the Mössbauer Spectra and the Spectra of Nuclear Quadrupole Resonance of the Superconducting Ceramic YBa<Subscript>2</Subscript>Cu<Subscript>3</Subscript>O<Subscript>7</Subscript>

The parameters of the Mössbauer spectra on ⁶⁷Cu(⁶⁷Zn), ⁶⁷Ga(⁶⁷Zn) isotopes, and the data of nuclear quadrupole resonance on an ¹⁷O isotope are anlayzed, and the lattice gradient of the electric field for the crystal lattice YBa₂Cu₃O₇ is calculated. It is shown that these parameters correspond to the model when the hole is predominantly in the sublattice of the oxygen chain.     

Probing the oxidation behavior of Ti2AlC MAX phase powders between 200 and 1000 °C

Oxidation of commercial Ti₂AlC MAX phase powders at 200–1000 °C has been investigated by XRD, XPS, SEM, STA and TGA coupled with FTIR. These powders are a mixture of Ti₂AlC, Ti₃AlC₂, TiC and Ti_1.2Al_0.8. Oxidation at 400 °C led to disappearance of carbide phases from Ti 2p, Al 2p and C 1s XPS spectra. At 600 °C, powders changed from dark grey to light grey with a significant volume increase due to crack formation. Powders were severely oxidized by detecting rutile with minor anatase TiO₂. At 800 °C, α-Al₂O₃ was detected while anatase transformed into rutile TiO₂. The cracks were healed and disappeared. At 1000 °C, the Ti₂AlC powders were fully oxidized into rutile TiO₂ and α-Al₂O₃ with a change of powder color from light grey to yellow. FTIR detected the release of C as CO₂ from 200 °C onwards but with additional CO above 800 °C.     

Micro- and nanocomposite particles of the Cu–TiO<Subscript>2</Subscript> system

The micro- and nanocomposite particles of the Cu–TiO₂ system are synthesized using the laser scanning of a heliumlike film. A model of nanostructure formation on a dielectric surface is proposed.     

Identification of Δ<Superscript>7</Superscript> phytosterols and phytosteryl glucosides in the wood and bark of several <Emphasis Type="Italic">Acacia</Emphasis> speciesphytosterols and phytosteryl glucosides in the wood and bark of several <Emphasis Type="Italic">Acacia</Emphasis> species

The wood and bark of four Acacia species growing in Portugal, namely, A. longifolia, A. dealbata, A. melanoxylon, and A. retinodes, were investigated for their sterol content. The lipids fractions of the different wood and bark samples were isolated, and the sterols were identified and quantified by GC-MS. Two Δ⁷ sterols, specifically, spinasterol and dihydrospinasterol, were the main sterols found in considerable amounts, particularly in wood tissues (more than 0.5 g/kg of dry wood in the case of A. melanoxylon and A. retinodes). The corresponding unusual steryl glucosides were also identified in significant amounts in the wood and bark extracts.     

STudy of the physicomechanical properties of modified raw materials of Al<Subscript>2</Subscript>O<Subscript>3</Subscript> – SIC – C composites based on HAC and ACPB

Results are given for a study of the dependence of apparent density and ultimate strength in compression on the quantity of silica and form of modifying addition (Al, Si, B and mixtures of them) for materials of the composition Al₂O₃ – SiC – C based on high-alumina cement and aluminochromium phosphate binder after low-temperature (400°C) heat treatment. It is established that the most efficient form the point of view of compaction and strengthening of raw material of corundum-graphite refractory is addition of aluminum powder.