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胆汁反流性胃炎是开展纤维胃镜以来发现的疾病,深入研究其病因病机,对指导中医临床治疗用药,提高疗效具有重要意义。通过对胆汁反流性胃炎的病因病机进行中医理论的探讨,认为脾虚为致病之本,肝郁是致病之标,肝脾不和是病机的关键。 相似文献
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朱荩雯 《中华临床医学卫生杂志》2007,5(3):3-4,2
目的观察中成药阿魏酸钠片联合西药氟桂利嗪胶囊治疗偏头痛的临床疗效。方法将81例符合国际头痛协会（IHS）制定的偏头痛诊断标准的患者，随机分成两组，接受阿魏酸钠片联合氟桂利嗪胶囊及单用氟桂利嗪胶囊的对比治疗，连用3个月，随访1年。结果两组总有效率有显著性差异（P〈0．05），控制复发率也有显著性差异（P〈0．05）。结论本疗法不仅疗效显著，而且对控制复发也有明显作用，疗法简单易行，副作用少，可作为偏头痛的常规用药。 相似文献
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Na Li Xin-Ning Bao Yong-Jun Guo Shi-Zhong Yang Ying-Cheng Li Bo-Zhong Mu 《RSC advances》2018,8(41):22986
The alkali free surfactant–polymer flooding system with ultralow interfacial tension is a challenge in enhanced oil recovery at present. A novel alkali free binary flooding system of a biobased zwitterionic surfactant and hydrophobically associating polymer with ultralow interfacial tension at a low surfactant dosage was studied in this paper.A novel alkali free binary flooding system of a biobased zwitterionic surfactant and hydrophobically associating polymer with ultralow interfacial tension at a low surfactant dosage was studied in this paper.Ternary alkali-surfactant–polymer (ASP) flooding, as one of the representative chemical methods, has been successfully applied in enhanced oil recovery (EOR) in last few decades.1–4 However, the alkali in the ASP system simultaneously resulted in the reduction of reservoir permeability due to the dispersion and migration of clay and the alkaline scaling in formation.5 Alkali-free binary surfactant–polymer (SP) flooding with ultralow interfacial tension (≤10−3 mN m−1) is a promising approach among tertiary oil recovery methods. It has received much attention from both the scientific and industrial communities since two-thirds of crude oil were still trapped in oil reservoirs after primary and secondary oil recovery.1,6 Over the past few years, SP flooding has been conducted on modest scales and significantly improved EOR efficiency in Daqing Oilfield7 and Shengli Oilfield,8 China. In the absence of alkali, however, the most traditional surfactant–polymer flooding systems could not reach the required ultralow interfacial tension, and may consequently fail in EOR.2,9,10In the present work, we developed an alkali free binary flooding system consisting of the biobased zwitterionic surfactant and hydrophobically associating polymer with ultralow interfacial tension. Zwitterionic surfactants usually have lower critical micelle concentration (CMC),11 better water solubility12 and satisfied interfacial tensions.13 The biobased zwitterionic surfactant (N-phenyloctade-canoicamidopropyl-N,N-dimethyl-carboxylbetaine, POAPMB) synthesized using renewable feedstock in our laboratory demonstrated excellent surface/interfacial activity and environmental biodegradability, and its CMC was 5.58 × 10−6 mol L−1.14 The hydrophobically associating polymer (AP-P3) was synthesized in the laboratory as described in published literature.5 The structures of POAPMB and hydrophobically associating polymer were illustrated in Fig. 1. The interfacial tension (IFT), viscosity and phase behavior of the biobased zwitterionic surfactant/hydrophobically associating polymer binary system were investigated, which is, to the best of our knowledge, the first report about the SP flooding of alkali free biobased zwitterionic surfactant and hydrophobically associating polymer flooding system.Open in a separate windowFig. 1Structures of POAPMB and hydrophobically associating polymer.Unless otherwise specified, the POAPMB/AP-P3 system configured by Daqing simulated formation water (downhole temperature 45 °C) consisted of 0.50 g L−1 POAPMB (∼0.95 mM) and 1.50 g L−1 AP-P3 in the experiment. The interfacial tensions were measured by a spinning drop interfacial tensiometer at 45 °C. The IFT between simulated formation water and Daqing crude oil (the acid value: 0.06 mg KOH per g) was 9.9 mN m−1 at 45 °C. The viscosity of POAPMB/AP-P3 system was measured by a rheometer at 45 °C.Dynamic interfacial tensions between Daqing crude oil and different concentrations of surfactant solutions alone and in the presence of 1.50 g L−1 AP-P3 were showed in Fig. 2a and b (ESI Fig. 1a and b†). The ultralow IFT could be achieved at a concentration as low as 0.05 g L−1 (Fig. 2a and ESI Fig. 1a†), which is fifty times lower than that of the sugar-based anionic-nonionic surfactant15 (ESI Table 11†). Most of alkylbenzene sulfonates16 and propyl sulfobetaine17 can not achieve ultralow IFT without alkali.Open in a separate windowFig. 2The IFT between crude oil and different concentrations of POAPMB solutions (a) and in the presence of 1.50 g L−1 AP-P3 (b) (n = 3).For the binary system POAPMB/AP-P3 (1.50 g L−1) solution, the ultralow IFT was reached when the POAPMB concentrations ranged from 0.50 g L−1 to 3.00 g L−1 (Fig. 2b and ESI Fig. 1b†), which implies that the POAPMB/AP-P3 system is promisingly applicable in tertiary oil recovery. The addition of the polymer increased minimum transient IFT (IFTmin), and it is possibly due to the formation of mixed micelle-like associations on the interface led to decline of interfacial free surfactant molecules and the lose adsorption.6,9 In addition, it took more time to achieve the balance of IFT in the presence of the polymer. Compared with nonionic surfactant10 (ESI Table 11†), POAPMB/AP-P3 binary system can effectively reduce interfacial tensions.In addition to the ultralow IFT, the performances of anti-dilution, stability, adsorption resistance, temperature adaptability, and salt tolerance also play an important role in SP flooding technology. For the anti-dilution, POAPMB/AP-P3 system achieved ultralow IFT when the solution was diluted to one eighth (†). For 3.00 g L−1 POAPMB solution with 1.50 g L−1 AP-P3, ultralow IFT could be achieved even if it was diluted to one fortieth (ESI Table 2†).The minimum IFTs and the equilibrium IFTs between crude oil and POAPMB/AP-P3 system diluted (n = 3)
Open in a separate window 5 (ESI Table 11†).The IFTmin and IFTequ between crude oil and POAPMB/AP-P3 system with aging time (45 °C, n = 3)
Open in a separate windowThe binary system and Daqing oil sands were mixed at the weight fraction ratio of 9/1. The mixture was shook at 45 °C for 24 h by shaking water bath. The IFT between Daqing crude oil and the supernatants was then measured. If the value of IFT was below 0.01 mN m−1, fresh sands were added to the remaining supernatants at the same weight fraction. Repeat the above operation until the IFT of the solution was above 0.01 mN m−1. The total number of times that an ultralow IFT achieved were taken as the measurement for evaluating the resistance of a surfactant formulation against adsorption by sandstone.2 For the binary system, ultralow IFT was achieved after two cycles (†). Ultralow IFT was achieved after three cycles for the solution of 3.00 g L−1 (about 5.71 mM) POAPMB with 1.50 g L−1 AP-P3 (ESI Table 3†). It is recognized that the Daqing oil sands are negatively charged. Due to electrostatic attraction, hydrogen bonding, ion-exchange, chain–chain interaction, covalent bonding, and hydrophobic bonding, as well as solvation of various species,18,19 the saturated adsorption of different types of surfactants followed an order of anionic < nonionic < zwitterionic < cationic surfactants.2,9,10,20 Yan et al.2 reported that a nonionic/zwitterionic formulation with polyacrylamide achieved four times the ultralow IFT (ESI Table 11†).The IFTmin and IFTequ between crude oil and POAPMB/AP-P3 system after adsorption (45 °C, n = 3)
Open in a separate window Fig. 3 showed IFTs of POAPMB/AP-P3 system at different temperatures. The IFTmin of POAPMB/AP-P3 system was below 0.01 mN m−1 at 50 °C to 90 °C (Fig. 3 and ESI Fig. 2†). But the IFTequ showed an upward trend and roughly increased for both systems with increasing temperature. The IFTequ at 80 °C and 90 °C were above 0.01 mN m−1 (Fig. 3 and ESI Fig. 2†). Probably because the hydrophobic interactions among surfactant molecules became weaker with the temperature increase,21 making the array of the interfacial surfactant molecule looser.18,22 Moreover, when the temperature of the system increased and the molecular motion speeds up accordingly, the solvent molecules in the interface layer may be increased.21 The viscosity of the binary system was 32.8 mPa s at 70 °C (ESI Table 6†).Open in a separate windowFig. 3Effects of temperatures on the IFTs between crude oil and POAPMB/AP-P3 system (n = 3).The effects of NaCl and Ca2+ concentration (CaCl2 was added in the solution) on IFT were showed in Fig. 4 and and55 (ESI Fig. 3 and 4†). Ultralow IFTequ was achieved when the concentration of NaCl below 15.00 g L−1 and the concentration of Ca2+ below 400 mg L−1. The excessive electrolyte ions destroy the hydration film around the hydrophilic head, promoting the surfactants on the oil/water interface to transfer to the oil phase and the interface tension increases with a reduction of aggregation degree.15,23 The salinities of most oil fields are normally below 16.00 g L−1 and the concentrations of Ca2+ are below 300 mg L−1 14,24 in Chinese oilfields. The present results suggested that POAPMB/AP-P3 system had strong electrolyte tolerance, and it could remain good interfacial properties in a wide range of salinity. The viscosity retention rates of POAPMB/AP-P3 system were 55% and 77% at the conditions of 12.50 g L−1 NaCl and 200 mg L−1 Ca2+, respectively (ESI Table 7 and 8†), which implied a possibility for its application in most oil fields in China.Open in a separate windowFig. 4Effects of concentrations of NaCl on the IFTs between crude oil and POAPMB/AP-P3 system (n = 3).Open in a separate windowFig. 5Effects of concentrations of Ca2+ on the IFTs between crude oil and POAPMB/AP-P3 system (n = 3). 5 reported that the initial viscosity retention rate of fatty acid disulfonate with hydrophobically associating polyacrylamide was 67% (ESI Table 11†). The addition of POAPMB lowered the viscosity of polymer. Biggs et al. found that with the concentration of sodium dodecyl sulfate increased the viscosity of hydrophobically modified polyacrylamide solution rose first and felled later and accordingly proposed a three-stage model.25 The same phenomenon was observed in cation surfactant,26 zwitterionic surfactant27 and nonionic28–30 surfactants and hydrophobically associating polymer systems. The surfactant may incorporate to the polymer molecules in the form of spherical micelles.31 When the concentration of surfactant was high, hydrophobic region of hydrophobically associating polymer became solubilized by a single micelle. As a result, intermolecular association effects weakened and polymer network was destroyed (Region III),25 and the viscosity decreased. The viscosity of both solutions decreased over time. The viscosity retention rate after 30 days was 72% for POAPMB/AP-P3 system, which implied a good viscosity stability.The viscosities of the polymer solution with aging time and POAPMB/AP-P3 system with aging time (45 °C, n = 3)
Open in a separate windowMicroemulsions are thermodynamically stable, macroscopically homogeneous mixtures of water, oil and one or more amphiphilic compounds. Microscopically, the surfactant molecules may form a film separating the two incompatible solvents into two domains.32 An O/W middle phase microemulsion can been observed in the tube. “Solubilization ratio for oil (water) is defined as the ratio of the solubilized oil (water) volume to the surfactant volume in the microemulsion phase”.33 Solubilization ratio for oil need to be higher than 10 as an effective surfactant flooding.33 According to observation and calculation, the solubilization ratio for oil was 40 for POAPMB/AP-P3 system (Fig. 6). The particle size measurement (ESI Table 9†) showed that the polymer aggregates were formed in the bottom phase, and the surfactant molecules stayed in the middle phase as reported.33 The zeta potential of middle phase microemulsion was −50.4 mV (ESI Table 10†), which implied the surfactant molecules formed an electrical double layer at the oil-aqueous interface.34 In general, values greater than ±30 mV suggested a good stability of the emulsions.34,35 In addition, emulsification of the crude oil to form the O/W emulsion is beneficial for high recovery.2Open in a separate windowFig. 6Photograph of crude-oil-in-simulated formation water middle phase microemulsion taken after 3 weeks of settling 45 °C. 相似文献
| Dilution multiple | 0.5 g L−1 POAPMB + 1.5 g L−1 AP-P3 IFTmin (mN m−1) | 0.5 g L−1 POAPMB + 1.5 g L−1 AP-P3 IFTequ (mN m−1) |
|---|---|---|
| 1 | (4.1 ± 0.3) × 10−3 | (8.7 ± 0.3) × 10−3 |
| 2 | (5.9 ± 0.4) × 10−4 | (1.6 ± 0.1) × 10−3 |
| 3 | (6.4 ± 0.5) × 10−4 | (1.5 ± 0.1) × 10−3 |
| 4 | (1.6 ± 0.3) × 10−4 | (2.6 ± 0.2) × 10−3 |
| 5 | (2.9 ± 0.2) × 10−5 | (4.1 ± 0.3) × 10−3 |
| 6 | (9.7 ± 0.6) × 10−5 | (8.0 ± 0.4) × 10−4 |
| 7 | (1.2 ± 0.2) × 10−4 | (6.7 ± 0.5) × 10−3 |
| 8 | (2.4 ± 0.3) × 10−4 | (2.4 ± 0.3) × 10−4 |
| 9 | (5.1 ± 0.3) × 10−1 | (9.9 ± 0.4) × 10−1 |
| Days | 0.50 g L−1 POAPMB + 1.50 g L−1 AP-P3 IFTmin (mN m−1) | 0.50 g L−1 POAPMB + 1.50 g L−1 AP-P3 IFTequ (mN m−1) |
|---|---|---|
| 0 | (4.1 ± 0.3) × 10−3 | (8.7 ± 0.3) × 10−3 |
| 2 | (3.1 ± 0.2) × 10−3 | (6.6 ± 0.4) × 10−3 |
| 4 | (2.0 ± 0.2) × 10−4 | (3.3 ± 0.3) × 10−3 |
| 7 | (1.5 ± 0.1) × 10−4 | (3.0 ± 0.1) × 10−3 |
| 10 | (2.3 ± 0.3) × 10−4 | (3.7 ± 0.2) × 10−3 |
| 15 | (2.0 ± 0.4) × 10−4 | (3.4 ± 0.3) × 10−3 |
| 30 | (7.2 ± 0.5) × 10−5 | (8.0 ± 0.5) × 10−4 |
| 60 | (3.5 ± 0.3) × 10−3 | (9.2 ± 0.6) × 10−3 |
| 100 | (4.8 ± 0.3) × 10−3 | (3.7 ± 0.3) × 10−2 |
| Times | 0.5 g L−1 POAPMB + 1.5 g L−1 AP-P3 IFTmin (mN m−1) | 0.5 g L−1 POAPMB + 1.5 g L−1 AP-P3 IFTequ (mN m−1) |
|---|---|---|
| 1 | (4.4 ± 0.4) × 10−4 | (4.4 ± 0.3) × 10−4 |
| 2 | (3.5 ± 0.3) × 10−3 | (3.9 ± 0.2) × 10−3 |
| 3 | (8.8 ± 0.4) × 10−1 | (9.7 ± 0.2) × 10−1 |
| Days | 1.5 g L−1 AP-P3 viscosity (mPa s) | 0.5 g L−1 POAPMB + 1.5 g L−1 AP-P3 viscosity (mPa s) |
|---|---|---|
| 0 | 58.4 ± 0.5 | 46.8 ± 0.4 |
| 2 | 51.6 ± 0.4 | 44.9 ± 0.3 |
| 4 | 52.4 ± 0.4 | 40.9 ± 0.3 |
| 7 | 51.6 ± 0.5 | 42.0 ± 0.4 |
| 10 | 50.6 ± 0.4 | 38.2 ± 0.2 |
| 15 | 50.2 ± 0.4 | 37.1 ± 0.3 |
| 30 | 43.0 ± 0.3 | 33.8 ± 0.2 |
| 60 | 35.1 ± 0.3 | 26.2 ± 0.2 |
| 100 | 32.7 ± 0.2 | 22.4 ± 0.1 |
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二维功能材料的制备方法常见的有以下几种：（1）机械剥离或液相剥离具有面间弱相互作用、面内强共价键合作用的层状材料生成单层或少数层的二维材料;（2）化学合成方法;（3） Langmuir-Blodgett单分子膜技术法;（4）层层自组装法;（5）化学气相沉积法;（6）分子束外延法和（7）原子层沉积技术法。这些材料及其有机-高分子衍生物具有独特的结构特征和优异的性质,在场效应晶体管、光调制器、锁模和Q开关激光、光限幅、信息和能源存储、射频器件、化学传感器等领域具有重要的潜在应用价值。近年来,除了众所周知的石墨烯外,其他诸如类石墨烯的无机纳米材料（六方氮化硼、过渡金属卤化物、石墨化氮化碳、层状金属氧化物等）、二维聚合物、金属-有机框架、钙钛矿、黑磷等二维材料也被广泛研究或探索。开发或探索更多二维材料应用的关键是设计和制备新颖的二维材料和它们的有机-高分子衍生物。在不久的将来,兼具规模经济和功能行为的二维材料化学的突破将极大地驱动新型二维材料应用领域的拓展。本文综述了二维材料的基本概念、研究进展、亟待解决的关键问题和未来的发展趋势。 相似文献
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目的：探讨原发性肝癌（ primary liver cancer , PLC）切除术后保肝药联合应用与肝功能恢复之间的相关性,为临床治疗提供合理建议。方法选取我院2009年1月至2010年12月诊断为PLC并行肝脏肿瘤切除术的病历120份进行回顾性分析,记录齐全能够进行有效分析的为83例。依据《中国国家处方集》（2010）和药物作用机制将保肝药分为6类：A＝抗炎类,B＝稳定膜系统类,C＝结合解毒类,D＝改善供能类,E＝促进再生类,F＝其他类。结果（1）A＋D治疗方案与C＋D治疗方案比较,总胆红素k值的P＝0．046,门冬氨酸氨基转移酶k值的P＝0．035,C＋D治疗方案优于A＋D方案;（2）总胆红素的k值与门冬氨酸氨基转移酶的k值存在正相关,P＜0．01;（3）总胆红素k值和门冬氨酸氨基转移酶的k值与肝门阻断时间、肝硬化类型等因素不相关。结论原发性肝癌行肝脏肿瘤切除术后,C＋D治疗方案比A＋D治疗方案更能促进肝功能的恢复。 相似文献
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目的 筛选牙周炎患者组织中的差异表达miRNA,探讨其生物学功能以及参与的信号通路。方法 通过对微阵列数据库GSE54710中的158例牙周炎患者和40例健康人的牙龈组织中的基因芯片数据进行生物信息学分析,筛选差异表达miRNA,并预测参与的生物学功能和信号通路。采用SPSS 19.0软件包对数据进行统计学分析。结果 5种miRNAs（hsa-miR-451、hsa-miR-223、hsa-miR-486-5p、hsa-miR-3917、hsa-miR-671-5p）显著上调,4种miRNAs（hsa-miR-203、hsa-miR-210、hsa-miR-1246、hsa-miR-1260 ）显著下调。其中,hsa-miR-1260的靶基因584个,hsa-miR-451的靶基因139个。KEGG通路富集分析显示,hsa -miR-1260靶基因显著富集到TGF-beta等12条信号通路,hsa-miR-451靶基因显著富集到17条信号通路。结论 得到牙周炎组织中miRNAs的表达谱,牙周炎诱导的hsa-miR-1260和hsa-miR-451可能在牙周炎的生理病理学中起到关键作用。 相似文献