顶空气相色谱法测定长春西汀缓释片中丙酮残留量

目的：建立顶空气相色谱法测定长春西汀缓释片中丙酮残留量。方法：采用Agilent DB-624石英毛细管柱（30 m×0.32 mm×1.8μm）,以氮气为载气,顶空进样,进样口温度为230℃,FID检测器温度为250℃,程序升温,分流比为30∶1;结果：丙酮浓度在50~1000μg·m L-1范围内线性关系良好;低、中、高三个浓度水平的精密度（RSD）分别为0.9%、1.9%、0.6%;加样回收率分别为97.2%、94.6%、94.8%。结论：本方法简便、准确、专属性强、灵敏度高,可用于长春西汀缓释片中丙酮残留量的测定。

解决苯酚丙酮装置导流筒问题

高桥分公司漕泾200kt／a苯酚丙酮装置的E2231、E2422具有导流筒结构，其中E2231有两个导流筒，E2422有一个导流筒，三个导流筒的半顶角均为45°。按照GB150—1998规定，当导流筒的半顶角大于30°时，锥壳大端应采用带过渡段的折边结构。

Low palladium content CeO_(2)/ZnO composite for acetone sensor with sub-second response prepared by ultrasonic method

In practical applications,noble metal doping is often used to prepare high performance gas sensors,but more noble metal doping will lead to higher preparation costs.In this study,CeO_(2)/ZnO-Pd with low palladium content was prepared by ultrasonic method with fast response and high selectivity for acetone sensing.With the same amount of palladium added,the selectivity coefficient of CeO_(2)/ZnO-Pd is 1.88 times higher than that of the stirred sensor.Compared with the pure PdO-doped CeO_(2)/ZnO-PdO material,the content of Pd in CeO_(2)/ZnO-PdO is about 30%of that in CeO_(2)/ZnO-PdO,but the selectivity coefficient for acetone is 2.56 times higher.The CeO_(2)/ZnO-Pd sensor has a higher response(22.54)to 50×10^(−6) acetone at 300℃and the selectivity coefficient is 2.57 times that of the CeO_(2)/ZnO sensor.The sensor has a sub-second response time(0.6 s)and still has a 2.36 response to 330×10^(−9) of acetone.Ultrasonic doping makes Pd particles smaller and increases the contact area with gas.Meanwhile,the composition of n-p-n heterojunction and the synergistic effect of Pd/PdO improve the sensor performance.It shows that ultrasonic Pd doping provides a way to improve the utilization rate of doped metals and prepare highly selective gas sensors.

猪胃蛋白酶的生产工艺优化研究

在不影响胃蛋白酶活性的条件下,对现有的胃蛋白酶生产工艺加以改进,以降低胃蛋白酶产品的丙酮残留量。采用酸法提取胃蛋白酶,用丙酮作沉淀剂,且在2次固液分离中丙酮的加入量分别至溶液比轻度为0.95和0.87效果最佳,酶活收率为140.7 U/(g原料),产品收率为5.38%,比活为8.61 U/mg,5%胃蛋白酶溶液的浊度为1.270 A。利用将产品粉碎后再干燥的方法除去残留的丙酮,通过单因素试验和正交试验,以产品中丙酮残留量及比酶活作为指标,确定的最优工艺条件为:粉碎时间为45 s,干燥温度为20℃,干燥时间为6 h。该工艺参数下得到胃蛋白酶中丙酮残留量仅为0.75%,比酶活为8.72 U/mg,较未处理的胃蛋白酶产品丙酮残留量减少了40.5%,比酶活基本保持不变。

Measurement and correlation of solubility of meropenem trihydrate in binary(water＋acetone/tetrahydrofuran) solvent mixtures

The solubility of meropenem trihydrate in water+acetone mixtures and water+tetrahydrofuran mixtures were determined from T=(278.15 to 303.15) K by static method under atmospheric pressure.Effects of solvent composition and temperature on solubility of meropenem trihydrate were discussed.To extend the applicability of the solubility data,experimental solubility data in two kinds of binary solvent mixtures were correlated by the Apelblat equation and NIBS/Redlich–Kister model.It was found that the two models could satisfactorily correlate the experimental data and the Apelblat equation could give better correlation results.

Optoelectronic properties of new functionalized heteroleptic iridium complex

A new functionalized heteroleptic iridium complex coordinated with 1-phenylisoquinoline （1-piq） and a functionalized fl-diketone （G1）, Ir（1-piq）2G1, was synthesized and characterized by 1H-NMR, mass spectrometry and elemental analysis. The larger conjugation of the replacement of acetylacetone （acac） by a functionalizedβ-diketonate ligand led to a significant decrease in the HOMO level toward vacuum level, while Ir（1-piq）2G1 and Ir（1-piq）2（acac） showed red phosphorescent emissions of about 620 nm in dichloromethane solution. The phosphorescent polymer light-emitting devices were achieved, with the complexes incorporated with polyfluorene （PFO） as a host polymer doped with 30% of 5-（4-biphenylyl）-2-（4-tert-butylphenyl）-1,3,4-oxadiazole （PBD） as electron transport material. The energy transfer mechanism of the devices was also discussed. The lower EL performance of Ir（1-piq）2G1 is ascribed to the inter-ligand energy transfer, indicating that it is important to control the energy level of the cyclometalated and ancillary ligands.

Production of polyhydroxybutyrate by the marine photosynthetic bacterium Rhodovulum sulfidophilum P5

The effects of different NaCl concentrations, nitrogen sources, carbon sources, and carbon to nitrogen molar ratios on biomass accumulation and polyhydroxybutyrate （PHB） production were studied in batch cultures of the marine photosynthetic bacterium Rhodovulum sulfidophilum P5 under aerobic-dark conditions. The results show that the accumulation of PHB in strain P5 is a growth-associated process. Strain P5 had maximum biomass and PHB accumulation at 2%-3% NaCl, suggesting that the bacterium can maintain growth and potentially produce PHB at natural seawater salinity. In the nitrogen source test, the maximum biomass accumulation （8.10±0.09 g/L） and PHB production （1.11±0.13 g/L and 14.62%±2.25% of the cell dry weight） were observed when peptone and ammonium chloride were used as the sole nitrogen source. NH^-N was better for PHB production than other nitrogen sources. In the carbon source test, the maximum biomass concentration （7.65±0.05 g/L） was obtained with malic acid as the sole carbon source, whereas the maximum yield of PHB （5.03±0.18 g/L and 66.93%± 1.69% of the cell dry weight） was obtained with sodium pyruvate as the sole carbon source. In the carbon to nitrogen ratios test, sodium pyruvate and ammonium chloride were selected as the carbon and nitrogen sources, respectively. The best carbon to nitrogen molar ratio for biomass accumulation （8.77±0.58 g/L） and PHB production （6.07±0.25 g/L and 69.25%±2.05% of the cell dry weight） was 25. The results provide valuable data on the production of PHB by R. sulfidophilum P5 and further studies are on-going for best cell growth and PHB yield.