碱性清洗液pH值调节中模糊专家系统的应用

铁路运输罐车的清洗过程,由于工作方式和环境条件的影响,具有非线性和时变性等特点。针对该复杂过程,提出了专家模糊控制算法。解决了完整精确数学模型难建立的问题,并结合了操作工人的实际生产经验及专家规则,实现了对清洗液pH值的闭环控制。并用MATLAB进行了仿真,验证了此控制方案的可行性和有效性。

Solubilization of aluminum phosphate by specific Penicillium spp.

The solubilization of hardly soluble aluminum phosphate （AlPO4） by specific Penicillium spp. isolated from wheat rhizospheric soils was investigated in Pikovskaya agar and liquid medium, respectively. Most of the Penicillium isolates except P. sirnplicissimum AP 11 and P. variabile AP 15 developed clear transparent zone around the colony margin in plate assays. Results of broth assays show that the Penicillium isolates can efficiently solubilize aluminum phosphate in Pikovskaya liquid medium, and vary in their capabilities to release soluble phosphate from aluminum phosphate. All the isolates exhibit different abilities to lower the pH and increase the titratable acidity in the broth compared to the control. HPLC analysis shows that most of the isolates except the species of P. aurantiogriseum can excrete different concentrations of organic acids, including gluconic acid, citric acid, oxalic acid, malic acid and tartaric acids, in the broth. The release of soluble phosphate by the isolate P. oxalicum AP2, which is the best solubilizer of aluminum phosphate among the isolates, is accompanied by a significant drop of pH and an obvious rise of titratable acidity during 7 d of aluminum phosphate-solubilizing experiments. The effects of temperature, initial pH, concentration of aluminum phosphate and shaking speed on aluminum phosphate solubilization by P. oxalicum AP2 were also investigated, and the maximum contents of soluble phosphate released are recorded at temperature 30 ℃, initial pH 6, aluminum phosphate concentration 20 g/L, and shaking speed 160 r/min.

Effect of aggressive pH media on peat treated by cement and sodium silicate grout

The effects of aggressive peat nature (pH) on the strength of peat treated by cement and cement-sodium silicate grout were investigated by evaluating the changes in unconfined compressive strength,moisture content,and scanning electron microscopy (SEM) of samples with time in different pH media.The results indicate that peats treated by cement-silicate have higher strength than peats treated by cement,due to an increase in pH value of the media.Furthermore,cement and cement-silicate are highly effective in reducing the moisture content and void ratio of the treated peats.The microstructures of treated peats support the laboratory test results.

Characterization of the Gastric Intraluminal pH and Development of the Proventricular Deep Glands during Perinatal Period in the Ostrich

In this research, the state of the gastric secretion in 38 days old ostrich embryos and chicks of different age was investigated by determining the pH level in the stomach as well as the histological structure of the deep proventricular glands （gll. proventriculares profundi）. In both parts of the stomach, on the 38th day of embryonic development pH parameters were higher than in chicks after hatching. The proventricular deep gland lobules and secretory epithelium on the 38th day of embryonic development and on the day of hatching were comparatively poorly developed. The most rapid increase of the proportion of the secretory epithelium of the proventricular deep glands was observed just before hatching and during the first week after hatching, but having reached two weeks of age it did not increase any more. The obtained results allow making a conclusion that already on the day of hatching an intensive gastric juice secretion occurs in the proventricular deep glands regardless of the stage of their histological development. The gastric intraluminal pH parameters indicate that the gastric secretion increases with chicks advancing in age, however on the day of hatching this important gastric function is biologically rather complete.