稻茬免（少）耕小麦田除草技术试验研究

1995～1996年在稻茬免耕小麦田,进行了播前和播后药剂除草试验.结果表明,播前用41%草甘膦75ml/667m~2或20%百草枯100ml/667m~2防除杂草效果分别为96、94.1%.播后4天用10%甲黄隆4g/667m~2、10%甲黄隆4g/667m~2+25%异丙隆100g/667m~2.对总草株防效分别61.4、80.3%,明显优于50%丁草胺100ml/667m~2防效(44.2%).而在小麦苗2叶1心期用10%甲黄隆4g/667m~2、10%甲黄隆4g/667m~2+25%异丙隆100g/667m~2、10%甲·绿5g/667m~2、25%异丙隆250g/667m~2,对总草株防效分别达82.6、97.3、90.0、88.3%.且比播后土壤处理防效好,并对小麦较安全.示范推广应用中,将播前和播后药剂除草技术相结合,可有效控制稻茬免(少)耕小麦田草害.     

高底物浓度纤维乙醇同步糖化发酵工艺的比较

引言日益加剧的能源危机和环境污染,正迫使人们寻求新的可再生替代能源。纤维乙醇作为一种重要的生物质替代能源,经过近40多年的发展,已经具备了实现工业化生产的潜力。为了进一步降低纤     

A new route to functional polymers: Synthesis of functional polymer-supported esters from a weak acid ion exchange resin

Treatment of Amberlite IRC-50, a weak acid cation exchange resin containing methacrylic acid residues, with tetra-n-butylammonium hydroxide or benzyltrimethylammonium hydroxide gives the corresponding polymer-supported quaternary ammonium salts. These react smoothly, in nucleophilic substitution reactions, with a range of alkyl halides or sulfonates to give side chain esters with saturated hydrocarbon groups, with quaternary ammonium or sulfonate salt groups, with halide or alcohol groups at the terminus of spacer chains, with 1,2-diol groups, with acetylenic groups or with anthracene residues. These polymer-supported species have a variety of potential applications.     

Intimin及其受体Tir在致病性大肠杆菌致细胞线粒体功能障碍中的作用

目的探讨致病性大肠杆菌(Enteropathogenic Escherichia coli,EPEC)外膜蛋白Intimin及其受体Tir在EPEC致HeLa细胞线粒体功能障碍中的作用。方法将EPEC外膜蛋白Intimin及其受体Tir删除株、相应质粒互补株或染色体互补株感染HeLa细胞,用线粒体膜电位(Mitochondria membrane potential,MMP)检测试剂JC-1染色细胞线粒体,通过多功能酶标仪检测MMP水平,Western blot检测Intimin的表达及Tir的转位。结果与野生型菌株相比,Eae删除株和Tir删除株感染细胞的MMP功能显著减弱(P<0.05),Eae删除株功能能被质粒表达相应蛋白所互补,Tir删除株不能被质粒表达Tir互补,但可被染色质表达野生型Tir或TirY474S互补,而染色质TirS434A突变株不能引起明显的MMP下降。结论 Intimin和Tir是参与线粒体功能障碍的重要分子;TirS434在线粒体功能障碍中起重要作用。     

产纤维素酶细菌的筛选及其紫外诱变

采用刚果红脱色圈法初筛得到143株有纤维素酶活性的细菌。然后采用DNS法复筛得到纤维素酶酶活最高的6株细菌,进一步进行紫外诱变处理,获得酶活提高最大且具有遗传稳定性的菌株E140’,酶活为0．90IU·mL^-1,较出发菌株（0．68IU·mL^-1）提高了32．35％。表明采用刚果红脱色圈法和DNS法联合筛选并结合紫外诱变。可以获得纤维素酶活性高的细菌。     

柱后反应-离子色谱法测定饮用水中的溴酸盐

该文对臭氧处理水过程中可能产生的无机消毒副产物溴酸盐的检测方法进行探讨,用柱后反应-离子色谱测定溴酸盐的方法,溴酸盐的定量浓度可以低至0.5μg/L,较以前文献[4]所测浓度2.0μg/L为低,降低了方法的检测限.该方法具有较好的灵敏度,准确度和较低的检测限,能满足欧盟水质标准的检测要求.     

Polyamide 66 nanocomposites based on organoclays treated with thermally stable phosphonium salts

Purification of bentonite clays and their modification with two thermally stable (alkyl and aryl) phosphonium organic salts were investigated. The organoclays were subsequently melt compounded with Polyamide 66 (PA66), with and without the use of an elastomeric compatibilizer. The morphology, melt flow, thermal stability, and mechanical properties of the binary and ternary nanocomposites were studied. The bentonite clay was purified by sedimentation, resulting in higher cation exchange capacity and thermal stability in comparison with unpurified clay. These were then used in the synthesis of two thermally stable organoclays by replacing the interlayer sodium cations with two (alkyl and aryl) phosphonium surfactant cations to circumvent the problem of low temperature decomposition of quaternary ammonium organoclays usually used in polymer nanocomposites. The organoclay with aliphatic groups showed more compatibility with PA66 in comparison with the organoclay with aromatic groups. Thus, the use of organoclay with aliphatic groups resulted in nanocomposites with higher tensile strength, higher modulus, higher elongation at break, and higher impact strength in comparison with the nanocomposites produced from the organoclay with aromatic groups. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Electromechanical behavior of hybrid carbon/glass fiber composites with tension and bending

To understand the smart (i.e., good memory) characteristics of hybrid composites of carbon fibers (CFs) and glass fibers (GFs) with epoxy resin as a matrix, the changes in the electrical resistance of composites with tension and on bending were investigated. The electrical resistance behavior of composites under tension changed with the composition of the CF/GF, as well as with the applied strain. The fractional electrical resistance increased slowly with increasing strain within a relatively low strain region. However, with further loading it increased stepwise with the strain according to the fracture of the CF layers. The strain sensitivity of the samples increased with increasing CF weight percentage, and the samples incorporating more than 40 wt % CF showed a strain sensitivity higher than 1.54 for a single CF. The changes in the fractional electrical resistance with bending were not so dominant as those with tension. This difference was attributed to the action of two cancelling effects, which are the increasing and decreasing fractional electrical resistance due to tension and compression with bending, respectively. On recovery from a large applied bending, the fractional electrical resistance decreased slowly with unloading because of the increase of contacts between the fibers that resulted from the reorganization of ruptured CFs during the recovery. Even the composites incorporating a relatively small CF content showed an irreversible electrical resistance with both tension and bending. However, the strain sensitivity being larger with tension than with bending is ascribed to the difference in their mechanical behaviors. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 2447–2453, 2002     

Photoinitiated surface grafting of synthetic fibers,IV. Applications of textile dyes onto surface-photografted synthetic fibers

High-strength polyethylene (HSPE), polypropylene (PP), poly(ethylene terephthalate) (PET), and poly(vinyl alcohol) (PVA) textile yarns have been surface-photografted with various functional monomers, such as acrylic acid (AA), acrylamide (AM), glycidyl acrylate (GA) and 4-vinyl pyridine (VP), by means of the continuous presoaking process developed. The dyeing of these surface-modified yarns with various textile dyes has been investigated. In general, considerable improvements of dyeability have been observed. The dye adsorption of the surface-photografted fibers is influenced by many factors, such as type of fiber, amount and properties of the functional monomer grafted on the surface of the fibers, type of textile dye, etc. The fibers surface-grafted with a monomer containing basic groups, such as acrylamide and 4-vinyl pyridine, are efficiently dyed with an acid dye. Conversely, a fiber surface-grafted with acidic functional monomer is easily dyed to deep shades with basic dyes. The dye adsorption increases monotonically with increasing grafting measured in ESCA spectra as relative intensities of relevant lines. The ungrafted HSPE, PP and PET fibers can be dyed to some extent with certain dyes. In the present work, the dye adsorption increased by 3.4 times for HSPE fiber grafted with GA and dyed with the metal complex dye IO, by 7.9 times for PP fiber grafted with AA and dyed with the basic dye MB, by 6.1 times for PET with AM and with the direct dye SL, and by about 15.3 times for PVA with VP and with the acid dye TE.     

急性冠状动脉综合征患者血清中基质金属蛋白酶-2的表达

目的探讨急性冠状动脉综合征与血清基质金属蛋白酶-2(MMP-2)的相关性。方法应用酶图(SDS-PAGE en-zymograph)和Western blot方法检测50名急性冠脉综合征患者(27名ST段抬高急性心肌梗塞患者和23名不稳定性心绞痛患者)、20名稳定性心绞痛患者及40名正常对照者的血清MMP-2水平。结果急性心肌梗塞组血清MMP-2水平明显高于不稳定性心绞痛组;急性心肌梗塞组及不稳定性心绞痛组血清MMP-2水平明显高于正常对照组;稳定性心绞痛组与正常对照组差异无显著意义;急性心肌梗塞组及不稳定性心绞痛组血清MMP-2水平高于稳定性心绞痛组。结论急性冠脉综合征患者血清MMP-2水平明显升高,其水平可能与冠状动脉斑块的稳定性相关。     

超高效除草剂双草醚合成研究

研究了以硫脲和丙二醛二乙酯为主要起始原料，经缩合、甲基化、氯化、甲氧基化，氧化和缩合反应合成双草醚，在合成溶剂，催化剂，合成和分离方法上均有所改进，特别是最后一步缩合反应中用氢氧化钠代替氢化钠，宜于工业化生产，既有利于安全生产，又降低成本，产品含量95％，以硫脲计双草醚总收率为41％。     

纳米流体热管启动过程的试验研究

对Al2O3-水、CuO-水和SiO2-水3种纳米流体热管进行测试,给出了这3种纳米流体热管启动过程的温度分布,并与水热管进行比较。结果表明,纳米流体热管启动方式为均匀启动;与水热管相比,其加热段启动温度降低,启动时间缩短;加热段和冷凝段的温差相比水热管降低了2~5℃;加热段长度对其启动过程影响较小。     

Reaktionen mit N-Acylimino-dithiokohlensäurediestern

Reactions with N-Acylimino-dithiocarbonic-acid-diesters . Reactions of N-acylimino-dithiocarbonic-acid-S,S-diesters 1 with nucleophilic com-pounds present new possibilities to synthesize heterocycles. With amines 1a reacts by mono- and disubstitution, respectively, of methylthio-groups to isothioureas 2 and guanidines 3 , with 1,2-bi-nucleophilic arenes to benzoheterocycles 4 , with aliphatic diamines to imidazolidines 5 , pyrimidines 6 , diazepines 7 and the hexamethylene-diamine-derivatives 8. 1a reacts also with hydrazines to 1,2,4-triazoles 9 and with hydrazides to the thiosemicarbazones 10 or 1,3,4-oxadiazoles 11 . Heterocyclisations of 1 with guanidines, thiourea, salts of thiourea and amidines give the 1,3,5-triazines 12, 14, 15 and 16 . N-benzoyl-dithiocarbonic-acid-methylester -amid reacts with CH-acidic compounds to thiazoles 17 . The structures of the final products are determined by i.r.-, ¹H-n.m.r.-, u.v.- and mass-spectras.     

Statistical analysis of the concentrations of trace elements in a wide diversity of coals and its implications for understanding elemental modes of occurrence

Seventeen trace elements in 24 coals from worldwide deposits of differing ranks and sulfur contents were determined with the use of inductively coupled plasma optical emission spectrometry (ICP-OES), inductively coupled plasma mass spectrometry (ICP-MS), and flow injection (FI) ICP-MS. By examining multiple correlations between each trace element and three major elements, calcium, aluminum, and iron, we have found that thirteen trace elements (Li, Be, V, Cr, Mn, Ni, Cu, Zn, Ga, As, Se, Sr, and Ba) in the coals show significant correspondence. Elements correlating with aluminum are lithium, beryllium, vanadium, chromium, copper, gallium, and selenium; of these elements, vanadium, chromium, and copper also have a relationship with iron. Manganese, strontium and barium are correlated with calcium, while nickel, zinc, and arsenic are correlated with iron. In the geochemical and mineralogical senses, the significant correlation of a trace element with calcium reflects its common association with carbonate minerals for medium- to high-rank coals, while that with aluminum is implicative of the common association with aluminosilicate minerals and that with iron is characteristic of the association with sulfide minerals for high-sulfur coals, and with iron-bearing carbonate and clay minerals for low-sulfur coals. It is observed that most trace elements have more than one common association(s) in the 24 coals.     

The Emerging Role of Venetoclax-Based Treatments in Acute Lymphoblastic Leukemia

Venetoclax, a B-cell lymphoma (BCL-2) inhibitor, in combination with hypomethylating agents has become the new standard of care in elderly and unfit patients with acute myeloid leukemia, with significantly improved overall survival and quality of life. Studies of venetoclax combined with high-dose chemotherapy are emerging with evidence of higher rates of molecular remission. Recently, a growing number of publications bring forth the use of venetoclax in patients with acute lymphoblastic leukemia (ALL). In the current review, we present the biological rationale of BCL-2 inhibition in ALL, how the interplay of BH3 proteins modulate the response and the current clinical experience with various combinations.     

高温沉淀-水热法制备纳米氢氧化镁的性能

以氯化镁和氢氧化钠为原料,采用高温沉淀－水热法制备了高分散纳米片状氢氧化镁,采用扫描电子显微镜和X射线衍射仪对其形貌和晶体结构进行了表征,并在EVA中进行了初步应用研究。结果显示,该氢氧化镁分散性高,过滤性能好,与EVA的相容性好,且随水热时间的增加而进一步改善。经3 h水热改性的氢氧化镁,其填充量为50％的EVA混合物的转矩流变性能和力学性能优良,平衡扭矩为15 N·m,拉伸强度为11 MPa,断裂伸长率达到430％。     

Effects of Fat Content and Solid Fat Content on Caramel Texture Attributes

Fat plays an important role in caramel quality attributes, yet there is very little published work on how fat type and level influence caramel characteristics. Fat content was increased from 0 to 20 % to determine the effects of total fat content on caramel texture attributes such as cold flow, hardness, stickiness and tensile strength. Solid fat content (SFC) was also varied, from 3 to 90 %, by using commercially‐available fats with varied SFC at 22 °C. Cold flow decreased significantly with increased fat content, with greater effect for fats with higher SFC. Changes in caramel hardness with fat content were dependent on SFC. Hardness generally decreased with increasing fat content for the fats with low SFC, with the 3 % SFC fat softening the most. Hardness increased slightly with fat content for the hardest fat (90 % SFC). Stickiness generally decreased with increasing fat content although the effect was significantly higher with higher SFC fats. These results document that both fat content and SFC significantly influence caramel texture attributes.     

起爆方式对线性聚能装药射流形成的影响

以工程中常用的柔性切割器为研究对象,在不考虑端部效应的前提下,对3种起爆方式下线性聚能装药射流的形成过程进行了理论分析和数值模拟。结果表明,不同起爆方式下射流头部速度以端部面起爆最大,线起爆次之,端部点起爆在端面附近处形成的最低,但在距端面一定距离处,射流头部速度又能增大到与端部面起爆的速度相近。在射流内部,端部面起爆形成的射流在内部各点处的速度都是3种起爆方式中最大的,而端部点起爆时,则是随着距起爆点距离的增加由处处小于线起爆的射流速度分布转变到与端部面起爆相同的射流速度分布。在此基础上进一步提出3种起爆方式下线性聚能装药切割目标的数值模拟方法。     

三七叶甙制备原人参二醇及其差向异构体

三七叶总甙以c(NaOH)=2mol/L的氢氧化钠水溶液溶解,沸水浴加热8h进行水解,所得产物经乙酸乙酯萃取和硅胶柱层析分离得到原人参二醇。三七叶总甙与浓盐酸常温反应7h后,再用饱和碳酸钠溶液常温搅拌24h,所得产物经乙酸乙酯萃取和硅胶柱层析分离得到20(R) 原人参二醇。它们的结构经光谱分析及与文献对照得以鉴定。     

Pharmacological effects of arginine supplementation in rats with Walker 256 solid tumor

The effects of diet arginine supplementation for those with cancer are controversial. We evaluate the effects of dietetic supplementation with arginine over body weight, growth of tumor, metastatic dissemination, surviving time, amino acid metabolism, haematological changes of the rats with Walker 256 solid tumor. Intragastrical solutions with arginine at 4% and 6%, a standard diet (control) were administered to the animals. The supplementation with arginine was associated with a lower weight gain during the study period (p < 0.05). Surviving time of the rats with solid tumor did not vary significantly between the groups. The rate of metastase was lower in animals with Walker 256 solid tumor supplemented with arginine. The amino acid metabolism was estimulate in the animals after arginine supplementation at 4% and 6%, demonstrated by significant increases in blood levels of arginine, ornitine, citruline, proline and histidine when compared to the control group. Anaemia was less severe in the rats with Walker 256 solid tumor that received arginine supplementation. The results suggest that arginine 6% supplementation may have pharmacologic effect in rats with Walker 256 solid beyond the nutritional one.