在乙醛酸等化合物存在下乙二醛测定方法研究

本文介绍了对含有乙醛酸等羰基化合物的乙二醛水溶液,用分光尤度计测定乙二醛含量的方法。所用试剂为对硝基苯肼,显色剂为氫氧化四甲铵,加碱后3分钟内即可进行测定。乙二醛和乙醛酸浓度分别在10~(-6)—10~(-5)和0—10~(-4)mol/L之内,所测相对误差低于5.0％。本方法具有简便、快速和专一性较高的优点,可用于乙二醛制备乙醛酸工艺中,测定原料转化率之用。     

大孔树脂负载金属离子催化合成尿囊素

以乙二醛和尿素为原料，用FeSO4-H2O2催化氧化合成乙醛酸．将所得乙醛酸溶液在不经分离及大孔树脂负载的Ce(SO4)2固体酸催化剂存在的情况下，与尿素缩合制备尿囊素，实验考察了催化剂用量、反应温度、反应时间、原料配比、催化剂重复使用次数等因素对收率的影响．确定了最佳工艺条件，乙二醛氧化制乙醛酸的最佳工艺条件为反应温度15～20℃，n(乙二醛)：n(H2O2)=1：1．1，乙醛酸收率达82％．缩合反应的最佳工艺条件为Ce(SO。)2／大孔树脂催化剂用量为投料量的2％(质量比)，原料配比n(乙二醛)：n(尿素)=1：2．5，反应温度80℃，反应时间4h，产品尿囊素的收率可达54％，催化剂可重复使用11次以上。     

超临界CO2萃取-高速逆流色谱分离纯化丹皮中丹皮酚

采用超临界CO2提取中药丹皮中总丹皮酚,选择萃取温度、萃取压力、物料粒度为因素进行正交实验优选出超临界CO2萃取的最佳工艺条件：即物料粒度40～60目,萃取温度40℃,萃取压力20MPa,提取率可达90%以上。将萃取后的总丹皮酚应用高速逆流色谱进行分离纯化,两相溶剂系统为石油醚-乙酸乙酯-甲醇-水（1：0.4：1：0.4）,进样量为330mg,得180mg纯度为99.0%的丹皮酚。     

溶剂萃取法提取氨基酸

以二（２－乙基己基）磷酸（Ｐ２０４）为萃取剂，从沉淀胱氨酸后的毛发水解母液中提取复合氨基权。萃取过程的最佳工艺条件为：萃取剂组成Ｐ２０４（０．７５）－磺化煤油（０．１５）－乙基己醇（０．１０），室温，初始水相的ｐＨ值为２．５；用去离子水反萃取，萃取及反萃取的理论级数分别为８级和９级。     

微波辐射促进阔叶十大功劳叶萃取过程的研究

研究了在间歇式微波辅助萃取装置中提取阔叶十大功劳叶中的药用有效成分小檗碱。确定了萃取液中盐酸小檗碱的分析方法－－Al2O3柱层析－紫外分光光度法；分别选取了甲醇、乙醇、乙醇－水（V／V＝9：1）为溶剂；微波辐射时间为2min、4min、6min；处理比（g原料／mL溶剂）为1：40、1：60、1：80；利用正交实验设计考察了不同湿分原料的微波辅助萃取效率，得出了最优工艺条件；拍摄了典型萃取条件下萃取基本的透射电镜照片；探讨了微波辐射在植物原料萃取过程中对细胞结构破坏的机理。     

百合中秋水仙碱的分离及结构表征

采用超临界二氧化碳流体萃取百合中秋水仙碱, 用高效液相色谱法对萃取物中秋水仙碱的含量进行测定, 用重结晶、薄层色谱法对萃取物中秋水仙碱进行分离纯化, 纯化后的目标物用核磁共振和红外光谱进行表征. 研究结果表明： 采用高效液相色谱法测得萃取物中秋水仙碱的质量分数为6.4%, 纯化后分离收率为88%, 核磁共振和红外光谱表征的结果与标准物的图谱一致, 可见超临界流体萃取-测定-分离百合中秋水仙碱的方法具有较好的选择性.     

紫穗槐槐角精油的超临界CO2萃取及其成分分析

以萃取压力、萃取温度、分离温度与萃取时间为参数,对紫穗槐精油超临界CO₂萃取的最佳工艺条件进行了分析,并用气相色谱-质谱联用技术（GC-MS）对精油成分进行了鉴定.结果表明：萃取温度40 ℃、萃取压力25 MPa、分离温度38 ℃、萃取时间1.5 h为最佳工艺条件;精油含26种成分,占总萃取物含量的89.96%,主要包括α-蒎烯,月桂烯,α-雪松烯,β-桉叶油醇,反式-石竹烯,β-荜澄茄油烯等.     

微反应器中硝酸氧化乙二醛制备乙醛酸

针对传统硝酸氧化乙二醛制备乙醛酸存在周期长、选择性低等问题,本文提出了一种在微反应器中高选择性合成乙醛酸的方法。先将35%硝酸与40%乙二醛按照一定摩尔比输送到T形微混合器,在微通道和降膜微反应器中反应一段时间,将得到的乙醛酸反应液再和硝酸以一定摩尔比输送到T形微混合器、微通道以及降膜微反应器中,循环几次后得到最终反应液。结果表明:当硝酸(流速0.13 mL/min)与乙二醛(流速0.24 mL/min)初次混合的摩尔比为0.42∶1、硝酸(流速0.02 mL/min)与收集的乙醛酸反应液(流速0.24 mL/min)混合反应6次、T形微混合器与微通道的温度和停留时间分别为60℃和2 min、降膜微反应器反应温度为90℃时,乙二醛转化率为82%,乙醛酸选择性可达95%。     

乙醛酸的氧气-硝酸联合氧化制备及快速分析

在氧气辅助下,硝酸选择性氧化乙二醛制备了乙醛酸。在单因素试验基础上,通过高效液相色谱法,考察了通氧速率、保温反应温度、硝酸用量等因素对乙二醛转化率和乙醛酸收率的影响。研究结果表明:制备乙醛酸的最佳反应条件为通氧速率50 m L/min,保温反应温度60℃,硝酸与乙二醛物质的量比0. 59。在此条件下,乙二醛转化率为99. 00%,乙醛酸收率为84. 00%。与传统的硝酸氧化生产工艺相比,硝酸物质的量降低近10%,乙醛酸收率提高了5%以上。     

悬浮固化液相微萃取-高效液相色谱法分析生长素

建立基于悬浮固化液相微萃取预处理的高效液相色谱-荧光检测法（SFODME-HPLC-FLD）用于两种植物生长素（吲哚丙酸和吲哚丁酸）的分析. 实验考察各因素对萃取过程的影响,确定最佳条件：50 μL十二醇（纯）为萃取剂,20.0 mL样品溶液（pH 3.0）、0.25 g·mL^-1 NaCl、26 ℃、1 800 r·min^-1条件下萃取10 min. 结果表明,SFODME技术重现性好、灵敏度高,相对标准偏差小于8.66%,检测限为0.01 ng·mL^-1,线性范围为0.02~60 ng·mL^-1,加标回收率大于84.3%. 方法快速、稳定、环境友好,适用于实际样品的检测.     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

橡胶颗粒沥青混合料低温抗裂性试验研究

以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

Quantitative trait loci （QTLs） for quality traits related to protein and starch in wheat

Quality traits in wheat （Triticum aestirum L.） were studied by quantitative trait locus （QTL） analysis in a recombinant inbred line （RIL） population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross （ChSh）. Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.