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91.
Vodopivec M Podgornik A Berovic M Strancar A 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2003,795(1):105-113
The immobilization of the enzymes citrate lyase, malate dehydrogenase, isocitrate dehydrogenase and lactate dehydrogenase to CIM monolithic supports was performed. The long-term stability, reproducibility, and linear response range of the immobilized enzyme reactors were investigated along with the determination of the kinetic behavior of the enzymes immobilized on the CIM monoliths. The Michaelis-Menten constant K(m) and the turnover number k(3) of the immobilized enzymes were found to be flow-unaffected. Furthermore, the K(m) values of the soluble and immobilized enzyme were found to be comparable. Both facts indicate the absence of a diffusional limitation in immobilized CIM enzyme reactors. 相似文献
92.
93.
B. Delesalle R. Buscail J. Carbonne T. Courp V. Dufour S. Heussner A. Monaco M. Schrimm 《Coral reefs (Online)》1998,17(2):121-132
The export of carbon and carbonate from coral reefs was investigated through a multidisciplinary investigation of the hydrological,
geochemical, sedimentological and biological features of Tiahura reef on the northwestern coast of Moorea Island (French Polynesia).
The hydrology of the fore-reef is characterised by prevailing longshore western currents and a strong thermocline. As revealed
by turbidity structures (benthic and intermediate nepheloid layers) and by the amount of particles collected by near-bottom
sediment traps, horizontal and downslope advections of particles dominate over offshore vertical transport. The exported material
is rich in carbonate (ca. 80%) and poor in organic matter (ca. 4%). Sedimentation rates at 430 m depth, i.e. definitive export,
reached 209.6 mg m-2 d-1 (dry weight). Estimates of carbon and carbonates export for Tiahura reef also reported here represent respectively 47% and
21% of the organic and inorganic carbon produced within the reef. 相似文献
94.
John C. Petricciani 《Cytotechnology》1998,28(1-3):49-52
The first recognition of seriously contaminated biological products occurred almost 100 years ago. More recently, in the second
half of this century, the potential for contamination by viral and viral-like agents became obvious when the SV-40 virus was
identified as an endogenous agent in the cell cultures used to produce polio vaccines. The history of major contamination
incidents is reviewed, and current issues are discussed.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
95.
P. Gyaneshwar G. Naresh Kumar L.J. Parekh 《World journal of microbiology & biotechnology》1998,14(5):669-673
Native microflora present in the alkaline vertisols and two phosphate-solubilizing bacteria (PSB) isolated from soil using conventional screening media could not release phosphorus from alkaline Indian vertisol soils supplemented with carbon and nitrogen sources. The two PSBs could solubilize both rock phosphate and di-calcium phosphate in unbuffered media but failed to solubilize rock phosphate in buffered media. The organic acids secreted by these PSBs were 20–50 times less than that required to solubilize phosphorus from alkaline soil. 相似文献
96.
97.
Weili Zhou Bingtao WuQianhong She Lina ChiZhenjia Zhang 《Bioresource technology》2009,100(14):3471-3476
Investigation on a full-scale UASB treating industrial wastewater at a low organic loading rate (OLR) was conducted. Excellent treatment performance was achieved when treating the evaporator condensate of distillery wastewater at the OLR of less than 1 kg COD/m3 d. Anaerobic effluent could be discharged without further treatment, which saved energy and running cost considerably. GC–MS analysis showed that the soluble microbial products (SMPs) were decreased to a low level at the low OLR. The main SMP in the anaerobic effluent were long chain carbohydrates and esters, accounting for 55–65% of the total organic matters. Anaerobic SMP was more complex than the aerobic ones. 相似文献
98.
Small-scale concentration of viruses (sample volumes 1-10 L, here simulated with spiked 100 ml water samples) is an efficient, cost-effective way to identify optimal parameters for virus concentration. Viruses can be concentrated from water using filtration (electropositive, electronegative, glass wool or size exclusion), followed by secondary concentration with beef extract to release viruses from filter surfaces, and finally tertiary concentration resulting in a 5-30 ml volume virus concentrate. In order to identify optimal concentration procedures, two different electropositive filters were evaluated (a glass/cellulose filter [1MDS] and a nano-alumina/glass filter [NanoCeram]), as well as different secondary concentration techniques; the celite technique where three different celite particle sizes were evaluated (fine, medium and large) followed by comparing this technique with that of the established organic flocculation method. Various elution additives were also evaluated for their ability to enhance the release of adenovirus (AdV) particles from filter surfaces. Fine particle celite recovered similar levels of AdV40 and 41 to that of the established organic flocculation method when viral spikes were added during secondary concentration. The glass/cellulose filter recovered higher levels of both, AdV40 and 41, compared to that of a nano-alumina/glass fiber filter. Although not statistically significant, the addition of 0.1% sodium polyphosphate amended beef extract eluant recovered 10% more AdV particles compared to unamended beef extract. 相似文献
99.
根据2008年6月在吕泗渔场(31.90°N-32.10°N、121.70°E-121.95°E)海域生态环境调查资料,分析了该区饵料浮游动物种类分布、优势种、数量分布、多样性等特征。结果表明:该区共出现饵料浮游动物31种(不含浮游幼体和腔肠动物),种类数和丰度均以桡足类占据优势;该区总生物量均值为845.54mg.m-3,其中大潮时为895.58mg.m-3,分布趋势为北部高于南部,小潮时为795.49mg.m-3,分布趋势为中部较高;6月吕泗渔场饵料浮游动物优势种分别是真刺唇角水蚤(Labidocera euchaeta)、中华哲水蚤(Calanus sini-cus)、小拟哲水蚤(Paracalanus parvus)、太平洋纺锤水蚤(Acartia pacifica)、火腿许水蚤(Schmackeria poplesia)、长轴螺(Peraclis reticulata)、长额刺糠虾(Acanthomysis longirostris);大潮时真刺唇角水蚤和中华哲水蚤优势度最高均为0.19,小潮时真刺唇角水蚤优势度最高为0.40;在吕泗渔场,6月饵料浮游动物生物量较高,优势种数较多,反映出该渔场小黄鱼饵料环境的稳定性,为小黄鱼幼体生长提供了良好的饵料条件。 相似文献
100.
To elucidate the role of low molecular weight chelators in long-distance root-to-shoot transport of heavy metals in Indian
mustard, an “off-line” size exclusion high-performance liquid chromatography–graphite furnace atomic absorption spectrometry
was developed to investigate heavy metals associated with low molecular weight chelators in xylem saps of Indian mustard (Brassica juncea). The size exclusion chromatogram presented only the peaks with molecular weight for all xylem saps and directly indicated
the long-distance transport of phytochelatins (PCs) of Indian mustard under Cd stress. In the absence of Cd stress, only organic
acids and inorganic anions participated in the long-distance transport of Cd, but organic acids, inorganic anions, glutathione
(GSH), and cysteine might relate to the long-distance transport of Cu or Zn. In the presence of Cd stress, PCs were induced,
and Cd ions in xylem saps were associated with the induced PCs. As the Cd levels in nutrient solution increased, more Cd in
xylem saps adopted the form of PC–Cd. Although PCs might participate in the long-distance transport of Cd under Cd stress,
the majority of Cd was still transported by organic acids and inorganic anions in xylem vessels. Moreover, results indicated
the existence of complexation competition for GSH and cysteine between Cd and Cu (or Zn) and complexation competition for
Cd between PCs and GSH (or cysteine) in xylem vessels. Our work might be very useful for understanding the mechanism of long-distance
transport of heavy metals in hyperaccumulator. 相似文献