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1.
建立了高效液相色谱(HPLC)检测乳液和化妆水中芍药苷和葛根素的方法.样品经过甲醇超声提取,以质量分数为0.1%磷酸水溶液-乙腈洗脱,经C18反相色谱柱分离,二极管阵列检测器(DAD)检测,计算出2种草药成分含量.在最优化条件下,该方法对芍药苷和葛根素的相应线性范围在0.2~10.0μg·mL-1,在232 nm和250 nm处紫外吸收强度具有良好的线性关系,相关系数(R2)大于0.999.该方法的回收率在90.4%~103.9%之间,相对标准偏差(RSD)在1.53%~2.37%之间,芍药苷和葛根素在乳液和化妆水中的方法检出限分别是2 mg·kg-1和8 mg·kg-1.该方法适合快速、高效、准确测定乳液和化妆水中芍药苷和葛根素的含量.  相似文献   

2.
采用水热法合成了含混合配体的铜配合物[CuClPhen]+·[HL]-·2H2O(HL=5-硝基间苯二甲酸,Phen=1,10-菲咯啉),其结构由单晶X射线晶体学确定。标题化合物在三斜空间群P-1的晶体化合物。标题化合物的晶体数据:C32H24ClN5CuO8,Mr = 704.54,a = 10.4044(5),b = 12.3912(9),c = 12.4632(9)Å,α = 73.859(6),β = 85.036(5),γ = 78.202(5)°,V = 1510.09(17) Å3,Z = 2, T = 293(2) K,Dc = 1.549 g/cm3,μ(Mo) = 0.874 mm-1,F(000) = 720.0,R = 0.0554,wR = 0.1434,GOF = 1.098。当用作超级电容器电极材料时,所制备的配合物具有高比电容、良好的循环稳定性和优良的倍率性能。在1mol/L KOH溶液中,最大比电容可达到69 F/g。在2 A/g电流密度下,10000次循环后比电容保持率为72%。标题化合物是一种潜在的红色光致发光材料。  相似文献   

3.
过渡族金属基二维纳米材料作为电催化析氧反应(oxygen evolution reaction, OER)催化剂具有巨大的潜力。通过原位电沉积法,在泡沫镍基底表面制备了二维层状镍铁双氢氧化物(NiFe-LDH)和氧硫化钼Mo(OS)x纳米片异质结构。NiFe LDH/Mo(OS)x电极在1 M KOH溶液中表现出优异的OER性能和长效稳定性,在10 mA/cm2电流密度下过电势仅为220 mV。在100、500 mA/cm2的高电流密度下,也能达到253、304 mV的低过电势。研究结果表明,NiFe-LDH/Mo(OS)x电极优异的OER性能归因于Mo(OS)x和NiFe LDH的协同作用,极大地促进了Fe2+向Fe3+活性物质的转化,并促进了氧空位的形成。这种协同制备方法为合理构建和设计异质结构电催化剂,实现高效的水分解提供了帮助。  相似文献   

4.
采用混合溶剂双相浸取法处理精对苯二甲酸(PTA)的氧化残渣,对残渣中的苯甲酸和Co2+、Mn2+进行有效分离回收. 研究结果表明: 在浸取温度为30℃,乙酸异丁酯∶正庚烷∶0.2mol·L-1硫酸水溶液∶干残渣=3∶3∶8∶1(质量比),浸取时间为30min的条件下,有机相中苯甲酸浸取率达83%以上,纯度高于95%,水相中Co2+、Mn2+的浸取率分别为98.82%和99.31%. 最后提出一个从氧化残渣中回收苯甲酸和Co2+、Mn2+的概念流程,实现残渣的资源化回收利用.  相似文献   

5.
疏水缔合阳离子淀粉的制备及其对滇池含藻水的絮凝研究   总被引:1,自引:0,他引:1  
 采用氧化还原引发体系,通过反相悬浮聚合技术,进行四元St-OA-AM-DMDAAC聚合,合成疏水缔合阳离子淀粉;研究其对滇池含藻水的絮凝.结果表明:在m(St):m(AM):m(DMDAAC):m(OA)=4:8:1.5:0.6时,40℃反应3 h,单体转化率达92.4%,接枝率63.8%,黏均相对分子质量3.26×106,阳离子化度7.3%;在处理pH为6.0的滇池含藻水时,加入量为15 mg/L时,透光率及CODCr去除率分别达93.5%,71.3%;市售PAM-C为91.3%及69.2%;同时疏水缔合阳离子淀粉用量在10-25 mg/L,pH在6-10范围内,对滇池含藻水有较好的絮凝效果.  相似文献   

6.
采用水热法合成了含混合配体的铜配合物[CuLPhen]n(HL=5-硝基间苯二甲酸,Phen=1,10-菲咯啉),其结构由单晶X射线晶体学确定。标题化合物在单斜空间群P21/c中结晶。标题化合物的晶体数据:C20H11N3CuO6,Mr=106.57,a =10.6619(3),b =12.5760(4),c =13.0550(3)Å,α =90,β=95.463(3),γ =90°,V =1742.50(9)Å3,Z =4,T=293(2)K,Dc =1.726 g/cm3,μ(MoKα)=0.301 mm-1,F(000)=51.0,R =0.0380,wR =0.07,GOF =1.026。当用作超级电容器电极材料时,所制备的配合物具有高比电容、良好的循环稳定性和优良的倍率性能。具体来说,在1 mol/L KOH溶液中,最大比电容可达到225 F/g。在5 a/g电流密度下,5000次循环后比电容保持率为67.31%。  相似文献   

7.
利用乳液聚合法,以甲基丙烯酸甲酯为单体,过硫酸铵为引发剂,不饱和超支化聚(酰胺-酯)为交联剂,染料隐色体为芯材,合成了交联的聚甲基丙烯酸甲酯热敏型微胶囊乳液.系统研究了乳液聚合过程中各因素对单体转化率和乳液聚合稳定性的影响.结果表明:保护胶体质量分数为3.5%~4.5%,芯壁质量比为1∶8,引发剂和交联剂质量分数分别为0.6%和6.0%,聚合反应温度为70℃时,单体转化率较高,乳液的稳定性较好;在最佳条件下制备的微胶囊粒径分布均匀,平均粒径为0.19μm.  相似文献   

8.
目的 探索川明参外观色泽与多个指标成分间的关系,为快速、高效筛选优质川明参药材提供参考。方法 以不同商品规格川明参药材为研究对象,首先利用分光测色仪测定川明参粉末色度值,然后采用热浸法、硫酸-苯酚法以及超高效液相色谱法分别测定水溶性浸出物、醇溶性浸出物、多糖、欧前胡素等指标成分质量分数,最后使用IBM SPSS Statistics 26软件分析色度值与各指标成分间的相关性。结果 川明参粉末颜色值L*与醇溶性浸出物、水溶性浸出物以及欧前胡素质量分数呈极显著负相关(P<0.01),与多糖质量分数呈显著负相关(P<0.05);ΔE*ab与水溶性浸出物及欧前胡素质量分数呈极显著负相关(P<0.01),与醇溶性浸出物、多糖质量分数呈显著负相关(P<0.05);a*b*与醇溶性浸出物、水溶性浸出物、欧前胡素质量分数呈极显著正相关(P<0.01),与多糖质量分数呈显著正相关。结论 色度值可作为快速判断评价川明参药材质量的指标,为全面评价川明参药材品质提供科学依据。  相似文献   

9.
采用单因子梯度试验法,设定20(I)、28(II)和40kHz(III)3个不同低频率超声波试验组,以不进行超声波作用为对照组,研究超声波对养殖水体中浮游植物群落结构的影响. 40d的试验结果表明:对照组浮游植物的丰度为各组最高,试验组II、III中,浮游植物丰度分别为3.8×105、2.3×105 ind·L-1,显著低于对照组(P<0.05). 共鉴定到浮游植物种类属数为16个,数目大小依次为试验组I>试验组II>试验组III>对照组. 试验组I中Shannon wiener多样性指数(H)、Margalef丰富度指数(D)分别达1.661±0.055和1.071±0.020,为各组最高;试验组III中Pielou均匀度指数(J)达0.619±0.018,为各组最高;与对照组相比,施加20kHz超声波显著提高了养殖水体中浮游植物生物群落多样性(P<0.05).  相似文献   

10.
采用γ-甲基丙烯酰氧基丙基三甲氧基硅烷(MPS)对亲水型纳米SiO_2改性得到了MPS-SiO_2纳米粒子,将MPS-SiO_2纳米粒子进一步通过甲基丙烯酸甲酯(MMA)改性得到了PMMA-SiO_2纳米粒子。傅里叶转换红外光谱分析(FT-IR)和接触角测试表明纳米SiO_2改性成功。以亲水型纳米SiO_2、MPS-SiO_2、PMMA-SiO_2、疏水型纳米SiO_2 4种粒子作为乳化剂制备Pickering乳液,研究了油水比(体积比,全文同)、纳米SiO_2浓度、pH值、盐浓度对Pickering乳液稳定性的影响。结果显示:静置24 h后,油水比为1∶1时,质量分数为1%的亲水型纳米SiO_2、MPS-SiO_2、PMMA-SiO_2制备的乳液剩余体积分数依次为48%、80%、76%,表明2种改性后的纳米SiO_2的乳化性能显著增强;亲水型纳米SiO_2、MPS-SiO_2、PMMA-SiO_2制备的Pickering乳液最佳油水比为1∶1,疏水型纳米SiO_2制备的Pickering乳液最佳油水比为1∶2;4种纳米SiO_2粒子的乳化性能均随着其浓度的增加而增强;与其他3种粒子相比,PMMA-SiO_2制备的Pickering乳液受pH、盐浓度的影响较小。  相似文献   

11.
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.  相似文献   

12.
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.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
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.  相似文献   

14.
何延凌 《科技信息》2008,(4):258-258
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.  相似文献   

15.
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.  相似文献   

16.
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.  相似文献   

17.
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.  相似文献   

18.
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。  相似文献   

19.
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.  相似文献   

20.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

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