Traditional wastewater purifying methods are expensive and involve heavy facility investment, long time in treatment, and a requirement of large land area. In this paper, the purification of wastewater in small scale paper factories by using superconducting magnetic separation method is proposed. High Tc superconducting magnet cooled directly by cryocooler is designed. The centralmagnetic field can reach 1.48 Tesla and 3.92 Tesla in Direct Current (DC) and Alternating Current (AC) modes, respectively. In order to separate the nonmagnetic contaminants in the wastewater, the magnetic seeding particles modified by plasma polymerization technique were employed to realize the co -precipitation between contaminants and magnetic seeds. The results indicate that the Chemical Oxygen Demand (COD) of the wastewater can be reduced to 147 mg per liter after superconducting magnetic separation. The preparation of magnetic seeds by plasma polymerization is also discussed in detail.
Alcohol consumption has commonly been associated with semen parameters. However, the association between alcohol intake and semen parameters in primary and secondary infertile men remains unclear. In this study, 776 infertile men from China were grouped according to alcohol intake: abstainers, moderate drinkers (<9 units/week, up to approximately 100 g of ethanol) and heavy drinkers (≥9 units/week). Semen parameters, including semen volume, sperm concentration, total sperm count, progressive motility and normal morphology were investigated. Alcohol consumption and other lifestyle factors were assessed by questionnaire. Logistic regression models were applied. There was no significant association between alcohol consumption and semen parameters in men with primary infertility. Smaller testis volumes and lower sperm concentrations were found among moderate and heavy drinkers in the secondary infertility group than among abstainers. After adjustment for potential confounders, men with secondary infertility and heavy alcohol consumption had a higher risk of abnormal sperm concentrations (OR = 3.72; 95% CI, 1.04, 13.37). These findings suggest that alcohol intake may decrease sperm concentrations in men with secondary infertility, whereas no association was found in men with primary infertility. It may be beneficial for clinicians to advise male patients with secondary infertility who are seeking fertility treatment to avoid heavy alcohol consumption.
In this paper, a full localization 250W@4.5Khelium cryogenic refrigerator was commissioning up to nearly 470 hours.A step-by-step commissioning strategy about the stability of high and low pressure of refrigerator, cool-down processes in cold box and cooling capacity evaluation of refrigerator was carried out.Dynamic characteristics including the adjustment of pneumatic valves for the stability of high and low pressure, 300~4.5Ktemperature evolution of heat exchangers and turbine expanders in the cold box and cooling capacity fluctuation are experimentally discussed.The results are helpful to more precisely understand and commissioning hundred watts level helium cryogenic refrigerator.
The role of sexually transmitted infections (STIs) in semen parameters and male infertility is still a controversial area. Previous studies have found bacterial infection in a minority of infertile leukocytospermic males. This study aims to investigate the prevalence of STIs in semen from subfertile men with leukocytospermia (LCS) and without leukocytospermia (non-LCS) and their associations with sperm quality.Semen samples were collected from 195 men who asked for a fertility evaluation. Infection with the above 6 pathogens was assessed in each sample. Sperm quality was compared in subfertile men with and without LCS.The LCS group had significantly decreased semen volume, sperm concentration, progressive motility, total motility and normal morphology. The infection rates of Ureaplasma urealyticum (Uuu), Ureaplasma parvum (Uup), Mycoplasma hominis (MH), Mycoplasma genitalium (MG), Chlamydia trachomatis (CT), herpes simplex virus-2 (HSV-2) and Neisseria gonorrhoeae (NG) were 8.7 %, 21.0 %, 8.2 %, 2.1 %, 3.6 %, 1.0 and 0 %, respectively. The STI detection rates of patients with LCS were higher than those of the non-LCS group (52.3 % vs. 39.3 %), although there was no statistically significant difference between the two groups (P = 0.07). All semen parameters were not significantly different between LCS with STIs and without STIs, except the semen volume in the MG-infected patients with LCS was significantly lower than that in the noninfected group.LCS was associated with a reduction in semen quality, but was not associated with STIs.
Polymer coated Fe3O4 magnetic nano particles are selected as a magnetic seeding for superconducting magnetic separation to expand its scope of application in the wastewater treatment.Fe3O4 nano particles are synthesized at the room temperature,and the properties of nano materials are determined by X-ray Photoelectron Spectroscopy (XPS),Transmission Electron Microscopy (TEM) and Vibrating Sample Magnetometer (VSM).It is shown that the diameter of nano particles ranges from 6～8nm,the surface of Fe3O4 nano particles is overlaid with the polymeric chain with carboxyl,and the nano particles show super paramagnetic properties at the room temperature.The decontamination capacity of the wastewater is tested using the dyeing wastewater.Quality indicators,such as the turbidity and Chemical Oxygen Demand (COD) are measured before and after the treatment with polymer coated Fe3O4 nano particles and compared.It is shown that the magnetic nano particles can effectively purify the waste in the dyeing wastewater.
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