采油污水回注系统高效缓蚀阻垢剂

针对辽河油田某采油厂采油污水回注系统腐蚀结垢的严重情况,分析了注水系统水质各项指标,明确其腐蚀结垢原因。通过实验室动态模拟实验、现场试验等方法,筛选复配适合用于采油污水的缓蚀阻垢剂。实验结果表明,在药剂质量浓度45mg/L时,注水系统腐蚀速率为0.05mm/a,阻垢率达98%以上,能同时实现腐蚀与结垢的有效控制。该药剂投加剂量小,成本低,缓蚀阻垢效果优良,具有较好的推广应用价值。

长白山阔叶红松林的生态价位

森林生态系统的众多服务功能在近年来受到国际社会的广泛关注 ,生态系统服务评价方法和案例在国内外也有很多研究。在我国实施天然林保护工程的背景下 ,基于生态系统服务评价的思路 ,提出生态价位的相关概念和等级划分方法 ,并以长白山阔叶红松林为对象 ,进行了初步研究。生态价位是某生态系统的生态系统服务价值的大小程度 ,根据现实情况和研究目的不同 ,具体可以衍生出基本生态价位、现实生态价位、潜在生态价位及生态价位差的概念。应用这一组概念 ,不通过直接评价某一类型或某一地区的生态系统的各种服务价值 ,而是以相对比较的方式说明研究对象的生态价值的大小程度和分布特征。在长白山自然保护区和森林资源保护较好的两个林场范围内 ,选取不同群落和物理环境特征的典型阔叶红松林生态系统样地进行了调查 ,并对劲松林场进行区域性生态系统调查。研究结果表明 :在自然状态下 ,阔叶红松林的生态价位可以用基本生态价位表示 ,采用群落生物量作为基本生态价位的划分标准 ,分为 4级 :BEVL ,群落生物量 0～ 12 0 t/ hm2 ;BEVL ,群落生物量 12 0～ 2 4 0 t/ hm2 ;BEVL ,群落生物量 2 4 0～ 36 0 t/ hm2 ;BEVL ,群落生物量 >36 0 t/ hm2 ;对受到人为干扰的阔叶红松林 ,则根据其所处物理环境、群落结构

A miniaturized fluorescence detector with a windowless flow cell using a light-emitting diode

A miniaturized fluorescence detector using a high-brightness light-emitting diode as an excitation source was constructed and evaluated. A windowless flow cell based on a commercial four-port cross fitting was designed to reduce the stray-light level and to eliminate the optical alignment. The observed detection limit for fluorescein was 26 nM in the continuous-flow mode. The error in the reproducibility of the responses was evaluated by the FIA method, and was found to be within 2% RSD.

地衣芽孢杆菌GXN151的纤维素酶基因cel9A的序列分析及cel48A的定位

运用底物筛选法从地衣芽孢杆菌GXN151的基因文库中筛选到3类表达羧甲基纤维素酶活性的克隆。对克隆pGXNP11的测序表明其含有纤维素酶基因cel9A和cel48A的部分序列熏cel9A基因为1899bp熏可编码含633个氨基酸的内切葡聚糖酶cel9A熏cel9A的N-末端第21~456氨基酸形成家族9糖基水解酶催化功能域,第480~565氨基酸为家族3碳水化合物结合组件功能域,cel48A基因位于ce19A基因的下游,两者可能共用一个操纵子。cel48A基因编码一个外切纤维素酶熏通过染色体步移法将cel48A定位于4kbEcoRI片段上或10kbSalI片段上。

施肥与品种及其种子大小对冬小麦光合及叶绿素荧光特性的影响

以土垫旱耕人为土为供试土样,采用4个冬小麦品种、3种播种方式和4种施肥方式进行盆栽试验,研究施肥、品种和种子大小对小麦叶片光合和叶绿素荧光特性的影响.结果表明:(1)在开花期和灌浆期,旗叶叶绿素相对含量(SPAD值)均为NP配施最高,其平均值分别比对照显著增加17.83%和13.01%;NP配施条件下,在开花期和灌浆期SPAD均为大粒单播较高并显著高于小粒单播;开花期和灌浆期SPAD分别以远丰998和咸农39最高并显著高于其它品种,平均比最低的白芒麦分别高17.68%和18.75%.(2)对旗叶净光合速率来说,开花期的NP配施处理比对照略有下降,而单施N和P分别比对照显著降低13.03%和23.17%,灌浆期的平均值以NP配施最高且比对照显著提高6.95%;小偃6号在开花期显著高于其余品种4.01%~6.19%(P<0.05),而白芒麦和咸农39则在灌浆期具有较明显优势,均分别显著高于其余品种约16.60%~26.91%;在开花期和灌浆期,2种单播方式平均值相近且显著高于混播方式.(3)就叶片Fv/Fm和Fv/Fo值而言,NP配施明显高于其它施肥处理,且NP均衡供应时远丰998和混播方式具有明显优势.可见,氮...

田间管理措施减少玉米黄曲霉侵染的效果研究

[目的]减少黄曲霉侵染作物的几率。[方法]结合辽宁地区玉米生产状况,选择耕作措施、灌溉状况、施氮水平、作物品种、种植密度为影响因子,研究田间管理措施减少玉米田间黄曲霉种群侵染的效果。[结果]耕作措施能明显减少土壤中黄曲霉种群数量,与连作相比,轮作能降低土壤中黄曲霉数量。灌溉状况、施氮水平、作物品种和种植密度对土壤中黄曲霉数量没有影响。连作田间的黄曲霉平均菌落数大于轮作田间。灌溉状况对减少玉米黄曲霉侵染的效应优于其他因素。检测到黄曲霉的土壤含水量在5%~13%,当田间土壤含水量低于13%时,应及时灌溉。[结论]在田间管理中实施合理轮作和适时灌溉,可预防黄曲霉侵染。

有效开发我国畜禽粪便资源制造生物有机肥

介绍畜禽粪便制成生物有机肥的工艺流程及技术要点,并阐述其产生的环境效益与经济效益。

Synthesis and properties of two kinds of CPVC carboxylated ionic copolymers

In the present work, two kinds of CPVC carboxylated ionic copolymers were prepared by a new method. First, a graft copolymer (CPVC-cg-AA) comprising of polyacrylic acid (PAA) as branched chains and chlorinated polyvinyl chloride (CPVC) as backbone was synthesized by in-situ chlorinating graft copolymerization (ISCGC). Second, the acid groups of the graft copolymer were neutralized by sodium hydroxide and aluminium hydroxide, respectively in order to prepare carboxylated ionic copolymers.

北五味子不同炮制品中的木脂素类成分

研究北五味子炮制前后其中木脂素类成分的变化。采用电喷雾质谱(ESI-MS)以及高效液相色谱(HPLC)分别对经过不同方法炮制后的北五味子中木脂素类成分进行研究。北五味子经过不同方法炮制后,并没有新成分的生成,只是木脂素类成分含量有不同程度的变化。并对不同的炮制方法进行了比较。该方法准确、可靠,为北五味子不同炮制品的质量评价提供了一定的科学依据。

The time delay in electrochemical measurements of a finite-volume system

For a sphere electrode enclosed in finite-volume electrolyte, the measured current will deviate from the result predicted by the semi-infinite diffusion theory after some time. By random-walk simulation, we compared this time to the one needed for diffusion layer to reach electrolyte boundary, and revealed a clear signal delay of electrochemical current. Further we presented a quantitative description of this delay time. The simulation results suggested that the semi-infinite diffusion theory can even be applied when the theoretical diffusion layer grows to 1.28 electrolyte thicknesses, with an accuracy better than 0.5%. We attributed this time delay to the molecules' finite propagation velocity. Finally, we discussed how this delay can influence and facilitate the following electrochemical detection towards the nanometer and single-cell scale.

"Green synthesis" of monodisperse Pt nanoparticles and their catalytic properties

A green synthetic strategy to prepare monodisperse Pt nanoparticles was reported. Aminodextran acted as the reductive and protective agents, and Pt nanoparticles were characterized by UV/vis spectroscopy (UV-vis), Pt nanoparticles were conveniently obtained at one step. transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), and X-ray photoelectron spectroscopy (XPS). By changing the initial molar ratio of arninodextran to platinum precursor, Pt nanoparticles with different size were obtained. Amino groups of aminodextran could absorb on Pt nanoparticles surfaces and serve as a very good stabilizer. However, dextran without amino groups could not effectively stabilize Pt nanoparticles and aggregation of Pt nanoparticles were obtained. Catalytic activity of these Pt nanoparticles for the electron-transfer reaction between hexacyanoferrate (III) ions and thiosulfate ions was also studied, and they showed good catalytic efficiency.

Effect of doped dye on the charge-carrier transport and electroluminescent performance in molecularly doped polymer light-emitting diodes

The effects of the concentration of 10-(2-benzothiazolyl)-2,3,6,7-tetrahydro-1,1,7,7-tetramethyl-1H, 5H, 11H-(1)-benzopyropyrano(6, 78-i,j)quinolizin-11-one (C545T) as dopant in polyfluorene (PFO) on the charge-carrier transport and electroluminescence (EL) performance were investigated by steady-state and transient EL measurements. A fully green emission from C545T was observed and the EL performance depends strongly on the C545T concentration. The mobility in the C545T-doped PFO film was determined by transient EL. The dopant concentration dependence of the current-voltage relationship indicated clearly the carrier trapping by the C545T molecules. The mobility in C545T:PFO changed significantly with the C545T concentration, and showed a nontrivial dependence on the doping level. The behavior may be understood in terms of the formation of an additional energy disorder due to potential fluctuation caused by the Coulomb interaction of the randomly distributed doping molecules.

Soluble, saturated-red-light-emitting poly(p-phenylenevinylene) containing triphenylamine units and cyano groups

A conjugated poly(p-CN-phenylenevinylene) (PCNPV) containing both electron-donating triphenylamine units and electron-withdrawing cyano groups was prepared via Knoevenagel condensation in a good yield. Gel permeation chromatography suggested that the soluble polymer had a very high weight-average molecular weight of 309,000. A bright and saturated red emission was observed under UV excitation in solution and film. Cyclic voltammetry showed that the polymer presented quasi-reversible oxidation with a relatively low potential because of the triphenylamine unit. A single-layer indium tin oxide/PCNPV/Mg-Ag device emitted a bright red light (633 nm).