4万吨型6M50氢氮压缩机投运成功

我国第一台４万吨型６Ｍ５０氢氮压缩机于１９９８年元月投运一次成功,该机的开发过程、设计中主要技术参数和试车运情况表明,可作为更新换代产品,推广应用于中、小化肥厂。     

On the LiCo2/3Ni1/6Mn1/6O2 positive electrode material

LiCo_2/3Ni_1/6Mn_1/6O₂ layered oxide was synthesized by the combustion method that led to a crystalline phase with good homogeneity and low particles size. The structural properties of the prepared positive electrode material were investigated by performing XRD Rietveld refinement. Practically no Li/Ni mixing was detected evidencing that the studied compound adopts almost an ideal α-NaFeO₂ type structure. The Li||LiCo_2/3Ni_1/6Mn_1/6O₂ cell showed a discharge capacity of 199 mAh g⁻¹ when cycled in the 2.7–4.6 V potential range while the best cycling performances were recorded when the upper cut off is fixed at 4.5 V. Structural changes in Li_xCo_2/3Ni_1/6Mn_1/6O₂ with lithium electrochemical de-intercalation were studied using X-ray diffraction. This study clearly shows the existence of a solid solution domain in the 0.1 < x < 1.0 composition range while for x = 0.1, a new phase appears explaining the decrease of the electrochemical performance when the cell is cycled at high upper cut off voltage.     

1-溴-6-氰基-2-萘酚的合成

以2-萘酚(Ⅱ)为原料,经一锅两步反应制备6-溴-2-萘酚(Ⅳ),收率为89.0%;然后经氰化反应制备6-氰基-2-萘酚(Ⅴ),投料比n(CuCN)∶n(Ⅳ)=1.5∶1时收率为91.2%;最后分别用溴素和N-溴代丁二酰亚胺(NBS)两种不同的溴化试剂制备了1-溴-6-氰基-2-萘酚(Ⅰ)。以溴素为溴化试剂,乙酸为溶剂,n(Br2)∶n(Ⅴ)=1∶1,Ⅰ的收率为89.8%;该法成本较低,适合工业上大规模生产。以NBS为溴化试剂,乙腈为溶剂,n(NBS)∶n(Ⅴ)=1.00∶1.03,收率几乎定量(99.2%);该法条件温和,简单高效,可避免溴素易挥发和吸入毒性大的缺点,更适合实验室小规模合成。     

Integrin Alpha v Beta 6 (αvβ6) and Its Implications in Cancer Treatment

Integrins are necessary for cell adhesion, migration, and positioning. Essential for inducing signalling events for cell survival, proliferation, and differentiation, they also trigger a variety of signal transduction pathways involved in mediating invasion, metastasis, and squamous-cell carcinoma. Several recent studies have demonstrated that the up- and down-regulation of the expression of αv and other integrins can be a potent marker of malignant diseases and patient prognosis. This review focuses on an arginine-glycine-aspartic acid (RGD)-dependent integrin αVβ6, its biology, and its role in healthy humans. We examine the implications of αVβ6 in cancer progression and the promotion of epithelial-mesenchymal transition (EMT) by contributing to the activation of transforming growth factor beta TGF-β. Although αvβ6 is crucial for proper function in healthy people, it has also been validated as a target for cancer treatment. This review briefly considers aspects of targeting αVβ6 in the clinic via different therapeutic modalities.     

锂离子电池正极材料LiNi1/3Co1/3Mn1/3O2研究进展

层状结构材料LiNi1/3Co1/3Mn1/3O2具有高比容量、高循环性能、低成本和环保等优点,有望取代LiCoO2成为新一代锂离子电池正极材料。在介绍LiNi1/3Co1/3Mn1/3O2的结构特点和电化学反应特性的基础上,对其主要合成方法进行了详细评述,总结了该正极材料的阴阳离子掺杂、复合离子掺杂以及表面包覆改性等技术,指出国内外目前锂离子电池材料研究中存在的问题和未来的发展方向。     

二氧化钛负载磷钨钼杂多酸催化合成丁醛1，2-丙二醇缩醛

以二氧化钛负载磷钨钼杂多酸为催化剂,通过丁醛和1,2-丙二醇反应合成了丁醛1,2-丙二醇缩醛。系统考察了丁醛和1,2-丙二醇物质的量比、催化剂用量,以及反应时间诸因素对产品收率的影响。确定的适宜工艺条件为n(丁醛)∶n(1,2-丙二醇)=1∶1.7,催化剂用量为反应物料总质量的1.0%,带水剂环己烷8mL,反应时间1.0h。在此反应条件下,丁醛1,2-丙二醇缩醛的收率可达80.8%.     

Mutation of Leaf Senescence 1 Encoding a C2H2 Zinc Finger Protein Induces ROS Accumulation and Accelerates Leaf Senescence in Rice

Premature senescence of leaves causes a reduced yield and quality of rice by affecting plant growth and development. The regulatory mechanisms underlying early leaf senescence are still unclear. The Leaf senescence 1 (LS1) gene encodes a C2H2-type zinc finger protein that is localized to both the nucleus and cytoplasm. In this study, we constructed a rice mutant named leaf senescence 1 (ls1) with a premature leaf senescence phenotype using CRISPR/Cas9-mediated editing of the LS1 gene. The ls1 mutants exhibited premature leaf senescence and reduced chlorophyll content. The expression levels of LS1 were higher in mature or senescent leaves than that in young leaves. The contents of reactive oxygen species (ROS), malondialdehyde (MDA), and superoxide dismutase (SOD) were significantly increased and catalase (CAT) activity was remarkably reduced in the ls1 plants. Furthermore, a faster decrease in pigment content was detected in mutants than that in WT upon induction of complete darkness. TUNEL and staining experiments indicated severe DNA degradation and programmed cell death in the ls1 mutants, which suggested that excessive ROS may lead to leaf senescence and cell death in ls1 plants. Additionally, an RT-qPCR analysis revealed that most senescence-associated and ROS-scavenging genes were upregulated in the ls1 mutants compared with the WT. Collectively, our findings revealed that LS1 might regulate leaf development and function, and that disruption of LS1 function promotes ROS accumulation and accelerates leaf senescence and cell death in rice.     

硅钨钼杂多酸掺杂聚苯胺催化合成苹果酯

自制了硅钨钼杂多酸掺杂聚苯胺催化剂H4SiW6Mo6O40／PAn。以乙酰乙酸乙酯和乙二醇为原料合成苹果醋,较系统地研究了原料物质的量比、催化剂用量、反应时间诸因素对产品收率的影响。实验表明,合成苹果酯的适宜反应条件为n酯:n醇=1:1.9,催化剂的质量分数为o.8％,环己烷为带水剂,反应时间60min。上述条件下,苹果酯的收率为69.7％。     

Significantly reduced hysteresis in (Fe1/2Nb1/2)4+-modified 0.75Na1/2Bi1/2TiO3-0.25SrTiO3 lead-free piezoceramics with large strain

Aiming to get the NBT-based lead-free ceramic with high strain and low strain hysteresis for practical actuator applications, a solid solution of complex-ion (Fe_1/2Nb_1/2)⁴⁺doped 0.75Na_1/2Bi_1/2TiO₃-0.25SrTiO₃ ((Na_1/2Bi_1/2)_0.75Sr_0.25Ti_1-x(Fe_1/2Nb_1/2)_xO₃, abbreviated as NBST-100xFN) was designed and prepared, and its phase structure, micromorphology, ferroelectric, strain, dielectric and piezoelectric performances were systematically investigated. It was found that the incorporation of (Fe_1/2Nb_1/2)⁴⁺ causes a structure transition from the ferroelectric/relaxor (FE/RE) mixed phases to relaxor (RE) phase, increasing to a promising strain performance at x = 0.04 featured by not only a moderate strain value of 0.26%, corresponding normalized strain d₃₃* of 371 pm/V, but also a very small strain hysteresis of 22%. In addition, the NBST-4FN ceramic sample also exhibits an unexceptionable frequency-dependence of unipolar strain. This study provides a new understanding and design idea for the practical actuator application of high strain NBT-based lead-free ceramics with ultra-low hysteresis.     

Ca1-x（Li1/2Sm1/2）xTiO3体系微波介质陶瓷的低温烧结研究

采用传统陶瓷制备工艺,制备了添加10 wt%NCB(Na2O-CaO-B3O3)复合氧化物的Ca1-x(Li1/2Sm1/2)xTiO3(x=0.700～0.875)(CLST-x)体系陶瓷,研究了添加NCB后CLST-x体系的晶相组成、显微结构、烧结性能及微波介电性能与组成关系.研究结果表明,添加复合氧化物NCB后,CLST-x体系各组成主晶相仍呈斜方钙钛矿结构,没有其它杂相.添加10wt%NCB后,CLST-x体系陶瓷均可在950℃下烧结致密,在此温度下材料具有较佳的微波介电性能,其中CLST-0.875陶瓷在950℃保温5 h烧结后具有良好的微波介电性能:εr=63.6,Qf=1591 GHz,τ f=0 ppm/℃,可满足高介多层微波器件的设计要求.     

二氧化硅负载硅钨钼酸催化合成苹果酯

采用溶胶-凝胶法制备了二氧化硅负载硅钨钼酸催化剂。以其为催化剂,以乙酰乙酸乙酯和乙二醇为原料合成了苹果酯,探讨二氧化硅负载硅钨钼酸对苹果酯合成反应的催化活性。用正交实验法较系统地研究了反应物料配比、催化剂用量、带水剂用量、反应时间等因素对产物收率的影响。实验表明,二氧化硅负载硅钨钼酸是合成苹果酯的良好的催化剂,固定乙酰乙酸乙酯的用量为0.20mol,在n(乙酰乙酸乙酯):n(乙二醇)=1:1.5,催化剂用量为反应物料总质量的1.0%,带水剂环己烷8mL,反应时间60min的优化条件下,苹果酯的收率可达72.8%。     

1,6-二羟基-2-萘甲酸的合成研究

标题化合物是合成新型内分泌治疗剂的重要中间体,而其合成方法未见文献报道。以6-甲氧基-1-萘满酮为起始原料,经取代、氧化和水解3步反应得到目标产物,其结构经MS、~1HNMR、~(13)CNMR和IR确证。该路线原料廉价易得、操作简单、后处理方便,总收率达69.5%,适合工业化生产。     

MgF2包覆对正极材料LiNi1/3Co1/3Mn1/3O2性能的影响

通过浸渍法在正极材料LiNi1/3Co1/3Mn1/3O2的表面包覆MgF2,通过XRD、SEM、交流阻抗（EIS）分析、充放电测试研究了不同量MgF2包覆对LiNi1/3Co1/3Mn1/3O2正极材料的结构与电化学性能的影响。结果表明,MgF2以非晶态形式包覆于LiNi1/3Co1/3Mn1/3O2材料颗粒的表面,当包覆量为3%（物质的量分数,下同）时,三元正极材料具有优良的电化学性能,在3.0~4.6 V充放电范围内0.1C充放电倍率下,首次放电比容量为196.3 mA·h/g,1C循环50次后容量保持率为95.7%,55 ℃高温下1C循环50次后容量保持率为93.3%。     

层状结构LiNi1/3Co1/3Mn1/3O2正极材料制备过程与电化学性能

采用固相自引发基团置换法结合高温焙烧制备了亚μm级的LiNi1/3Co1/3Mn1/3O2正极材料。研究了热处理气氛、烧结时间对材料结构及性能的影响。研究结果表明在空气氛围下900℃焙烧20 h制备的LiNi1/3Co1/3Mn1/3O2正极材料具有最佳的电化学性能。     

锂镍钴锰氧正极材料的热聚合法制备及性能表征研究

经过几十年的发展,锂离子电池由于其在能量密度、循环寿命等方面的优势,在小心电子产品上获得了广泛的应用。在目前的商业化锂离子电池产业中,应用最广泛的正极材料是由Good enough等开发的LiCoO2材料,但是其有毒、热稳定性差等特点,导致其难以得到进一步的应用。因此,通过开发他们的复合材料成为了锂离子电池正极材料开发的主要研究方向之一。论文主要对LiNi1/3Co1/3Mn1/3O2材料的热聚合法制备及性能表征进行了一定的研究。     

1-(6-甲氧基-2-萘基)乙醇的合成

2 甲氧基萘经1,3 二溴 5,5 二甲基乙内酰脲盐酸催化溴化、Friedel Crafts乙酰化得到5 溴 6 甲氧基 2 乙酰基萘。在KOH、n BuOH和Et3N溶液中、w(Pd)=10%的Pd/C催化下,于60℃和常压下用H2氢化5 溴 6 甲氧基 2 乙酰基萘得1 (6 甲氧基 2 萘基)乙醇,收率98 7%。合成总收率94%(以2 甲氧基萘计)。