The powders transportation in the plasma transferred-arc space during the coaxial powder-feeding surface depositing process was theoretical evaluated. The axial acceleration and velocity of various particles in the ar...The powders transportation in the plasma transferred-arc space during the coaxial powder-feeding surface depositing process was theoretical evaluated. The axial acceleration and velocity of various particles in the arc column were described. According to the results from theoretical calculations, it was found that: (1) The powder’s transporting velocity is much lower than the plasma fluid’s; (2) The powders axial transporting velocity presents “valley-shape distribution” along plasma arc column traverse section when surfacing current is greater than 100 A . When the arc current exceeding 100 A , the powders coming through the center field of arc column will transport slower than the powder through the outer-around field of arc column. It is in the field where the temperature is in the range of 9 000 K ～11 000 K that the particles can achieve its maximum axial acceleration in the argon plasma space. (3) For the given powder mass density, the smaller its size is, the greater its acceleration and the greater its averaged transporting velocity will be in the arc space; (4) For the given powder size, the greater its mass density is, the smaller its acceleration and averaged velocity will be in the arc space.展开更多
Investigation of charge-transfer （CT） complexes of drugs has been recognized as an important phenomenon in understanding of the drug-receptor binding mechanism. Structural, thermal, morpholo-gical and biological beh...Investigation of charge-transfer （CT） complexes of drugs has been recognized as an important phenomenon in understanding of the drug-receptor binding mechanism. Structural, thermal, morpholo-gical and biological behavior of CT complexes formed between drug quinidine （Qui） as a donor and quinol （QL）, picric acid （PA） or dichlorodicyanobenzoquinone （DDQ） as acceptors were reported. The newly synthesized CT complexes have been spectroscopically characterized via elemental analysis;infrared （IR）, Raman, 1H NMR and electronic absorption spectroscopy; powder X-ray diffraction （PXRD）;thermogravimetric （TG） analysis and scanning electron microscopy （SEM）. It was found that the obtained complexes are nanoscale, semi-crystalline particles, thermally stable and spontaneous. The molecular composition of the obtained complexes was determined using spectrophotometric titration method and was found to be 1：1 ratios （donor：acceptor）. Finally, the biological activities of the obtained CT complexes were tested for their antibacterial activities. The results obtained herein are satisfactory for estimation of drug Qui in the pharmaceutical form展开更多
In this paper, the influence of processing parameters and powder binder content was studied and analysed on the properties of high loft nonwoven fabrics mainly using statistical analysis method. The relationship betwe...In this paper, the influence of processing parameters and powder binder content was studied and analysed on the properties of high loft nonwoven fabrics mainly using statistical analysis method. The relationship between the bulkiness and the warmth retention property was also tested. The analytical results reveal that the increase of the powder content, heating temperature and pressure will affect the tensile strength of nonwovens. Moreover, there are interactions between these parameters. The compression properties only change a little for a powder binder content of 15％—20％. However, with the increase of the heating temperature and pressure, the bulkiness and compression rate will reduce significantly. For the bulk density of high loft nonwoven fabrics, there exists a heat transter mechanism of air convection, but the higher the bulkiness of nonwovens, the larger the thickness and the better the warmth retention property of nonwoven fabrics.展开更多
文摘The powders transportation in the plasma transferred-arc space during the coaxial powder-feeding surface depositing process was theoretical evaluated. The axial acceleration and velocity of various particles in the arc column were described. According to the results from theoretical calculations, it was found that: (1) The powder’s transporting velocity is much lower than the plasma fluid’s; (2) The powders axial transporting velocity presents “valley-shape distribution” along plasma arc column traverse section when surfacing current is greater than 100 A . When the arc current exceeding 100 A , the powders coming through the center field of arc column will transport slower than the powder through the outer-around field of arc column. It is in the field where the temperature is in the range of 9 000 K ～11 000 K that the particles can achieve its maximum axial acceleration in the argon plasma space. (3) For the given powder mass density, the smaller its size is, the greater its acceleration and the greater its averaged transporting velocity will be in the arc space; (4) For the given powder size, the greater its mass density is, the smaller its acceleration and averaged velocity will be in the arc space.
基金supported by the National Natural Science Foundation of China(Nos.52071069,U1332110)the Liaoning Revitalization Talents Program,China(No.XLYC1902097)。
文摘Investigation of charge-transfer （CT） complexes of drugs has been recognized as an important phenomenon in understanding of the drug-receptor binding mechanism. Structural, thermal, morpholo-gical and biological behavior of CT complexes formed between drug quinidine （Qui） as a donor and quinol （QL）, picric acid （PA） or dichlorodicyanobenzoquinone （DDQ） as acceptors were reported. The newly synthesized CT complexes have been spectroscopically characterized via elemental analysis;infrared （IR）, Raman, 1H NMR and electronic absorption spectroscopy; powder X-ray diffraction （PXRD）;thermogravimetric （TG） analysis and scanning electron microscopy （SEM）. It was found that the obtained complexes are nanoscale, semi-crystalline particles, thermally stable and spontaneous. The molecular composition of the obtained complexes was determined using spectrophotometric titration method and was found to be 1：1 ratios （donor：acceptor）. Finally, the biological activities of the obtained CT complexes were tested for their antibacterial activities. The results obtained herein are satisfactory for estimation of drug Qui in the pharmaceutical form
文摘In this paper, the influence of processing parameters and powder binder content was studied and analysed on the properties of high loft nonwoven fabrics mainly using statistical analysis method. The relationship between the bulkiness and the warmth retention property was also tested. The analytical results reveal that the increase of the powder content, heating temperature and pressure will affect the tensile strength of nonwovens. Moreover, there are interactions between these parameters. The compression properties only change a little for a powder binder content of 15％—20％. However, with the increase of the heating temperature and pressure, the bulkiness and compression rate will reduce significantly. For the bulk density of high loft nonwoven fabrics, there exists a heat transter mechanism of air convection, but the higher the bulkiness of nonwovens, the larger the thickness and the better the warmth retention property of nonwoven fabrics.
