南海海绵Pachychalina sp.化学成分的研究(二)

从中国南海海绵Pachychalinasp．的正丁醇可溶部分分离获得一种核苷类化合物，其结构经IR、MS、1H－NMR、13C－NMR和1H－1HCOSY等实验分析确定为尿嘧啶脱氧核苷。该化合物是首次从我国南海海洋动物中分离获得的。     

南海软珊瑚Sarcophyton molle化学成分的研究(一)

从中国南海软珊瑚（Sarcophytonmolle）中分离到三个含氮化合物，其结构经紫外光谱（UV）、红外光谱（IR）、质谱（MS）和核磁共振（1HNMR、13CNMR）分析分别确定为神经酰胺Sinumeramide（Ⅰ），胸腺嘧啶（Ⅱ）和脱氧尿核嘧啶苷（Ⅲ）．本文是首次报导该种属软珊瑚的化学成分。     

南海软珊瑚Sarcophyton molle化学成分的研究

从中国南海软肉芝软珊瑚(Sarcophyton molle)中分离到七个化合物, 经紫外光谱(UV), 红外光谱(IR), 质谱(MS)和核磁共振光谱(1H NMR, 13C NMR)分析, 确定了其化学结构。它们是: 异新西松烯(1), (E, E, E)-7, 8-环氧-1-异丙基-4, 8, 12-三甲基-十四环-1,3, 11-三烯(2), 正十八烷酸(3), 鲨肝醇(4), 神经酰胺(5), 胸腺嘧啶(6), 胸腺嘧啶脱氧核苷(7)。其中化合物(2)为新化合物。本文是第一次报道软珊瑚Sarcophyton molle的化学成分。     

蛋氨酸合成酶催化反应研究VII.5-氨基-6-甲基尿嘧啶的合成研究

报道了5-氨基-6-甲基尿嘧啶简便的合成方法。该化合物以6-甲基尿嘧啶（2） 为起始物，经硝化或重氮化分别得到了中间体5-硝基-6-甲基尿嘧啶（3）和5-偶氮 苯基-6-甲基尿嘧啶(4)，化合物3和4经Na_S_2O_4还原，合成产物5-氨基-6-甲基尿 嘧啶（1）。     

南海佳丽鹿角珊瑚化学成分的研究(一)

从中国南海的一种石珊瑚一佳丽鹿角珊瑚（Acroporapuchro）的乙酸乙酯可溶部分获得两个有机化合物：正十六碳酸（Ⅰ）和（24S）－24-甲基胆甾醇（Ⅱ）。它们的结构是通过EIMS、IR、1HNMR、13CNMR和DEPT等实验分析确定的。其中纯的（24S）-24-甲基胆甾醇是首次从自然界大量获得。本文首次提供化合物（Ⅱ）的完整波谱数据。     

海绵Polymastia Sobustia的化学成份研究

首次报道从中国南海海绵Polymastiasobustia中分离得到5个纯化合物,经过MS,IR,1^HNMR,13^CNMR(DEPT),HMQC和HMBC等波谱技术鉴定为：豆甾-5-烯-7-羰基-3β-甾醇(1),N-(1-羟甲基-2,6-二羟基)十七烷基-5-羟基二十四脂肪酰胺(2),胸腺嘧啶(3),尿嘧啶(4),对羟基苯甲酸(5);其中化合物1和化合物2为新化合物。     

南海石珊瑚Pavona frondifera Dana化学成分的研究

从中国南海石珊瑚（PavonafrondiferaDana）中分离到两个化合物。经紫外（UV）、红外（IR）、核磁共振（1~HNMR，（13）~CNMR）、质谱（EIMS．HRMS）等波谱分析，确定其结构为：3－甲基－6－氨基嘌呤和胆甾醇。     

黑鳗藤中C_(21)甾体苷的分离和结构测定

从萝藦科植物黑鳗藤[Stephanotis mucronta (Blanco) Merr.]的藤茎中分离 到三个C_(21)甾体去氧糖苷（1） - （3）。通过化学降解和波谱技术，确定它们 的化学结构依次为：12-O-惕各酰基-20-O-乙酰基肉珊瑚苷元3-O-β-黄夹吡喃糖基 -（1→4）-β-磁麻吡喃糖基-（1→4）-β-磁麻吡喃糖苷（1），5，6-双氢-12-O- 乙酰基-20-O-惕各酰基肉珊瑚苷元3-O-β-黄夹吡喃糖基-（1→4）-β-磁麻吡喃糖 基-（1→4）-β-磁麻吡喃糖基（2）；12-O-乙酰基-20-O（N-甲基）邻氨基苯甲酰 基肉珊瑚甘元3-O-β-黄夹吡喃糖基-（1→4）-β-磁麻吡喃糖基-（1→4）-β-磁 麻吡喃糖甘（3）。其中1和2为新化合物，分别命名为mucronatoside A， mucrontoside B。3为已知化合物stephanoside E，系首次从该植物中分离得到。     

海绵Polymastia Sobustia的化学成分研究

首次报道从中国南海海绵Polymas tia sobustia中分离得到5个纯化合物,经过MS,IR,1H NMR,13C NMR (DEPT),HMQC和HMBC等波谱技术鉴定为：豆甾-5-烯-7-羰基-3β-甾醇(1 ),N-(1-羟甲基-2,6-二羟基)十七烷基-5-羟基二十四脂肪酰胺([ ST5”HZ 2),胸腺嘧啶(3),尿嘧啶(4[ ST5”BZ ),对羟基苯甲酸(5);其中化合物1和化合 物2为新化合物。     

蛋氨酸合成酶催化反应研究 VII.5-氨基-6-甲基尿嘧啶的合成研究

报道了 5 氨基 6 甲基尿嘧啶简便的合成方法 .该化合物以 6 甲基尿嘧啶 ( 2 )为起始物 ,经硝化或重氮化分别得到中间体 5 硝基 6 甲基尿嘧啶 ( 3 )和 5 偶氮苯基 6 甲基尿嘧啶 ( 4 ) ,化合物 3和 4经Na2 S2 O4还原 ,合成产物 5 氨基 6 甲基尿嘧啶 ( 1) .     

Water/i‐Propanol/n‐Butanol Microemulsions

Water and n‐butanol are immiscible. In this paper, i‐propanol was found to be surface active for both water and n‐butanol using surface tension measurement at 25.0±0.1°C, especially the system with i‐propanol in water displays a pronounced decrease in surface tension with a distinct inflexion point indicating aggregation. Investigation on phase behavior of water/i‐propanol/n‐butanol ternary system at 25.0±0.1°C showed i‐propanol could promote remarkably the miscibility of water and n‐butanol. Cyclic voltammetric technique was employed to locate the micro‐regions in single region, indicating the existence of three micro‐regions of water/n‐butanol, n‐butanol/water and bicontinuous region. Thus, a novel water/i‐propanol/n‐butanol microemulsion without general surfactant is expected to form. Dynamic light scattering also demonstrated the size (hydrodynamic diameter) distribution of the microemulsion, verifying further the formation of the microemulsion droplets.     

醇对水中DDAHPS分子聚集行为的影响

分别用稳态荧光猝灭技术和时间分辨荧光方法研究醇对两性表面活性剂 (十二烷基羟基磺化甜菜碱 ,DDAHPS)在水中聚集行为的影响 .结果表明 :在 4.0 0× 1 0 - 2 mol·L- 1DDAHPS水溶液中 ,随着正丁醇浓度的逐渐增大 ,表面活性剂的聚集数 (N)逐渐降低 .恒定醇的浓度为 2 .1 4× 1 0 - 2mol·L- 1时 ,醇碳链越长 ,N值越大 .与无醇体系相比 ,正丙醇和正丁醇使N值变小 ,正戊醇、正己醇和正庚醇使N值变大 .本文同时还测定了醇对微环境的极性 ,芘的荧光寿命及胶束内芘的激基缔合物形成效率的影响 .     

Dielectric and Calorimetric Characteristics of Bound and Free Water in Surfactant-Based Systems

The hydration behavior of the system polyoxyethylene (10) oleylalcohol [C_18:1 (EO)₁₀ or Brij 97]/water/dodecane/butanol (model system B) was investigated along a dilution line for which the respective weight ratio of dodecane:butanol:Brij 97 is 3:3:4. Two experimental methods were applied: time domain dielectric spectroscopy (TDDS) and sub-zero temperature differential scanning calorimetry (SZT-DSC). Two types of bound water (with melting peaks at -25 and -11°C) were detected by SZT-DSC (using the endothermic mode), whereas TDDS revealed only one such type. Nevertheless, roughly the same total amount of bound water was estimated from these two techniques. The average number of bound water molecules per ethylene oxide (EO) group, N_W/EO is 2.3 (TDDS data) or 2.5 (SZT-DSC data) in good agreement with the observation that 1–2 water layers are formed in the hydration of ethoxylated surfactants. We have also shown that butanol is involved in the formation of the bound water that melts at -25°C. We suggest that butanol molecules occupy binding sites within the second hydration shell, thereby reducing the expected total bound water content.     

Modeling and simulation of butanol separation from aqueous solutions using pervaporation

A study was conducted to separate butanol from an aqueous solution using pervaporation. A specially designed and manufactured cell was used to separate the butanol from butanol/water solutions of different butanol concentrations (6-8-11-16-20-50) g/l. A 250 cm³ butanol mixture at 33 °C was used to feed the cell, while the pressure of permeation side was about 0 bar. Results revealed that butanol concentration changes non-linearly during the first 3 h, and then proceeds linearly. The percentage of butanol removal increases with increasing feed concentration. The permeability of the used membrane was determined experimentally. A resistance in series model was used to simulate the pervaporation step. The butanol concentration in the feed during the pervaporation step was predicted by using the developed model. There is a fair agreement between butanol concentration in feeding tank of pervaporation cell both experimentally and predicted from the developed model.     

高效液相色谱法测定蜜桶花颗粒及其原植物来江藤中的麦角甾苷

建立了用高效液相色谱法测定蜜桶花颗粒及其原植物来江藤中麦角甾苷含量的方法。实验采用C18柱,以甲醇-0.5％醋酸水(体积比为42∶58)为流动相,在334 nm检测波长处检测。结果表明:麦角甾苷的进样量为0.029~2.038 μg时,进样量与色谱峰面积有良好的线性关系(r=0.9998);回收率为90.2%~93.8%;方法的精密度好,相对标准偏差(RSD)为0.34％(n=5)。方法快速、简便、准确,所测结果稳定、重现性好,可作为蜜桶花颗粒质量控制的一个检测方法。     

Spectrophotometric Determination of Water Content in Alcohol Organic Solvents

In this work, the absorption spectral characteristics and color‐change reaction mechanism of cobalt(II) chloride(CoCl₂) in alcohol organic solvents has been investigated in the presence of water, and then the optimum conditions for determining the water content in the solvents were selected. Results indicated that the absorption spectra of CoCl₂ in alcohols decreased with the increment of water content. At the maximum absorption wavelength of 656 nm, there were good linear relationships between the logarithm of the absorbance and the water content in organic solvents such as ethanol, n‐propanol, iso‐propanol and n‐butanol with related coefficients in the range of 0.9996?0.9998. For determining water content in organic solvents, this method is simple, rapid, sensitive, reproducible and environmentally friendly. Furthermore, the linear range cannot restrict determination of the water content in organic solvents. This method had been applied to determine the water content in ethanol and n‐butanol with satisfactory recovery of water in n‐butanol between 98.41%?101.29%.     

Evaporation of water through butanol films at the surface of supercooled sulfuric acid

The evaporation of water was monitored from 60, 64, and 68 wt % D(2)SO(4) at 213 K containing 0-0.18 M 1-butanol. Measurements were performed in vacuum using a mass spectrometer to record the velocities and relative fluxes of the desorbing D(2)O. In addition, the surface activity of butanol in the acid was characterized by hyperthermal argon atom scattering in conjunction with surface tension and butanol evaporation measurements. The segregated butyl species reach surface concentrations of approximately 4 x 10(14) cm(-2) (approximately 80% surface coverage) at 0.18 M bulk concentration. We find that the butyl films do not impede the evaporation of D(2)O from the acid to within the 5% uncertainty of the measurements. This result implies that small, soluble surfactants such as butanol form porous films that will not alter the growth or shrinkage of supercooled sulfuric acid droplets in the atmosphere.     

Ti-Si介孔分子筛的转晶与控制

以季铵盐型阳离子Gemini表面活性剂[C16H33(CH3)2N+(CH2)6N+(CH3)2C16H33]•2Br−(GEM16-6-16)为模板剂, 改变n(Ti)/n(Si)比值, 合成了系列Ti-Si介孔分子筛. X射线衍射(XRD)和透射电子显微镜(TEM)等表征结果表明, 在n(Ti)/n(Si)≤0.20时, 分子筛为高度有序六方介孔; 当 n(Ti)/n(Si)为 0.30时, 介孔转晶为立方相; 当n(Ti)/n(Si)为0.50时, 介孔转晶为层状相; n(Ti)/n(Si)为1.0时, 材料失去有序孔道结构. FT-IR分析表明, 在分子筛骨架间形成了Ti—O—Si键, 而且Ti—O—Si键的数目随n(Ti)/n(Si)的增加而增加, 达到一定饱和值后基本保持不变. 乙醇和丁醇对纯硅基介孔分子筛孔结构转晶控制作用呈现六方相→立方相→层状相递变规律, 因而钛酸正丁酯水解生成的丁醇对Ti-Si介孔分子筛转晶具有一定的控制作用.     

Monthly sea surface temperature records reconstructed by δ~(18)O of reef-building coral in the east of Hainan Island, South China Sea

Stable oxygen isotopic compositions of a coral colony of Porites lutea obtained on acore allowed the reconstruction of a 56-a (1943-1998) proxy record of the sea surface tempera-tures. This coral δ~(18)O data are from the east of Hainan Island water (22°20＇N, 110°39＇E), SouthChina Sea. The relationship between δ~(18)O in the skeletal aragonite carbonate and the sea surfacetemperature (SST) is SST=-5.36 δ~(18)O_(PDB)-3.51 (r=0.73, n=470), dδ~(18)O/d(SST)=-0.187‰/℃; and the thermometer was set at monthly resolution. The 56-a (1943-1998) proxy record of thesea surface temperatures reflected the same change trend in the northern part of South China Seaas the air temperature change trend in China.