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41.
Heavy metal precipitation by polycation-polyanion complex of PEI and its phosphonomethylated derivative 总被引:2,自引:0,他引:2
The removal of various heavy metal ions such as Cu2+, Co2+, Zn2+, Ni2+ and Pb2+ from aqueous solutions by precipitation with polyelectrolyte complex of PPEI and PEI was conducted. Heavy metal binding with PPEI was initially allowed to occur and then upon equilibration, PEI was added to initiate precipitation of the polyelectrolyte complex together with the heavy metal ion. The PPEI-PEI system was found effective for heavy metal scavenging purposes even in the presence of high concentrations of non-transition metal ions like Na+. Heavy metal concentration may be reduced beyond emission standards for industrial wastewaters. The PPEI-PEI polyelectrolyte complex was found to be more effective than traditional precipitation methods for the treatment of a representative electroless Ni plating waste solution. 相似文献
42.
A novel packet bit error rate (BER) and loss measurement method and system is proposed. A proposed 40 Gbit/s packet BER and loss measurement system is expressed in detail. A 40 Gbit/s BER and loss measurement with various conditions is demonstrated experimentally. In real time, only the payload part of a packet and burst stream with fluctuated guard time is evaluated. The BER and packet loss of a randomly received packet sequence due to routing and buffering can be also evaluated by the measurement system. A 10 Gbit/s packet BER and loss measurement with optical label switching, buffering, and preamble-free optical packet 3R are demonstrated experimentally. 相似文献
43.
A lateral current injection (LCI) multiquantum-well (MQW) laser having planar structure is proposed and its advantages compared with conventional vertical structure lasers. A LCI-MQW laser has been fabricated by using Si- and Zn-induced disordering of an MQW active layer. It is shown that a threshold current of 27 mA is achieved under pulsed current driven at room temperature and a very low stray capacitance of 0.27 pF is obtained at zero bias voltage 相似文献
44.
45.
Soichi Hirota Shuhei Inoue Takahito Inoue Yoshifumi Kawai Yasutaka Wada Takashi Noguchi Yukihiko Matsumura 《Korean Journal of Chemical Engineering》2016,33(4):1261-1266
Supercritical water gasification (SCWG) has attracted attention as a technology for utilizing wet biomass. We used a fluidized bed of alumina particles to prevent blockage of a SCWG reactor. A glucose solution was heated in the reactor with and without fluidized alumina particles. In the absence of alumina particles, char particles formed homogeneously in the reactor, but the use of a fluidized bed resulted in accumulation of char particles at the reactor’s exit rather than inside the reactor. Therefore, the fluidized bed was effective at preventing blockage of the reactor. However, the alumina particles did not remove deposits from the reactor’s walls. Instead, the fluidized bed caused larger char particles to form, preventing their adhesion to the reactor’s wall. 相似文献
46.
Tolulope Peter Saliu Nao Yazawa Kotaro Hashimoto Kenshu Miyata Ayane Kudo Mayu Horii Mion Kamesawa Thanutchaporn Kumrungsee Noriyuki Yanaka 《International journal of molecular sciences》2022,23(2)
The early detection of diabetic nephropathy (DN) in mice is necessary for the development of drugs and functional foods. The purpose of this study was to identify genes that are significantly upregulated in the early stage of DN progression and develop a novel model to non-invasively monitor disease progression within living animals using in vivo imaging technology. Streptozotocin (STZ) treatment has been widely used as a DN model; however, it also exhibits direct cytotoxicity to the kidneys. As it is important to distinguish between DN-related and STZ-induced nephropathy, in this study, we compared renal responses induced by the diabetic milieu with two types of STZ models: multiple low-dose STZ injections with a high-fat diet and two moderate-dose STZ injections to induce DN. We found 221 genes whose expression was significantly altered during DN development in both models and identified serum amyloid A3 (Saa3) as a candidate gene. Next, we applied the Saa3 promoter-driven luciferase reporter (Saa3-promoter luc mice) to these two STZ models and performed in vivo bioluminescent imaging to monitor the progression of renal pathology. In this study, to further exclude the possibility that the in vivo bioluminescence signal is related to renal cytotoxicity by STZ treatment, we injected insulin into Saa3-promoter luc mice and showed that insulin treatment could downregulate renal inflammatory responses with a decreased signal intensity of in vivo bioluminescence imaging. These results strongly suggest that Saa3 promoter activity is a potent non-invasive indicator that can be used to monitor DN progression and explore therapeutic agents and functional foods. 相似文献
47.
Masatake Ohnishi Atsuko Higuchi Setsuko Todoriki Keitaro Hiromi Wmikio Ohgushi Akiyoshi Wada 《Starch - St?rke》1990,42(7):273-276
Using the pH-jump (neutral to above 11) for Tyr-OH ionization as a probe, two glucoamylases from Rhizopus niveus and Rhizopus delemar were found to be caused the change in conformation, which is in a kinetically single step. The pH titration at pHs below 12 was carried out on a multidimensional correlation spectrophotometer. Correlations among the spectrophotometric properties: fluorescence, absorption and circular dichroism are almost identical for the two enzymes. These results suggest that conformational characteristics of the niveus enzyme is almost the same as that of the delemar one. 相似文献
48.
Inactivation of Bacillus spores by the combination of moderate heat and low hydrostatic pressure in ketchup and potage 总被引:2,自引:0,他引:2
Islam MS Inoue A Igura N Shimoda M Hayakawa I 《International journal of food microbiology》2006,107(2):124-130
The combination effect of moderate heat and low hydrostatic pressure (MHP) on the reduction of Bacillus subtilis, Bacillus coagulans and Geobacillus stearothermophilus spores in food materials (potage and ketchup) was investigated. These bacterial spores were suspended in potage (pH 7), acidified potage (pH 4), neutralized ketchup (pH 7) and ketchup (pH 4). The suspensions were treated with and without pressure (100 MPa) and temperatures of 65-85 degrees C for 3 to 12 h. The bacterial spores were inactivated by 4-8 log cycles during MHP treatment in potage, acidified potage and ketchup, whereas the spores were highly resistant to long time heat treatment in potage and neutralized ketchup. The degrees of spore destruction were mostly dependent on pH and medium composition during MHP treatment. The inactivation effect in MHP treatment was higher at the pH 7 than at pH 4 both in ketchup and potage. The bacterial spores showed higher inactivation in potage than ketchup during MHP treatment. 相似文献
49.
Plasma osmolality estimated from plasma concentrations of Na+, Cl-, K+, glucose, and urea was compared with measured osmolality in preweaned Holstein calves. When calves (n = 5) were fed only milk replacer after fasting for 24 h, measured osmolality fluctuated almost in parallel with estimated osmolality during the 8-h period after feeding, although estimated values were about 90% of measured values. When calves (n = 5) were fed only calf starter after fasting for more than 16 h, measured osmolality did not parallel the estimated osmolality during the 8-h period after feeding. Some factors depressed measured osmolality in the first 2 h. 相似文献
50.
A hybrid adsorption heat pump water heater has been studied for domestic use. It is a water heater with dual heat sources, and it combines the performances of adsorption heat pumps and conventional gas boilers. Moreover, functional adsorbent material‐zeolite (FAM‐Z02, Mitsubishi Chemicals) and water are a new adsorption pair for adsorption heat pumps. This article describes the operation, design, and performance analysis of one such water‐heating device. The experimental results showed that the hybrid water heater in the whole year has a stable COP even at low ambient temperature. The hybrid water heater can thus achieve high energy efficiency. 相似文献