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41.
1 INTRODUCTIONResin in pulpprocessisanadvancedtech niqueofextracting goldwithoutfilter ,inwhichgoldisdirectlyextractedfromcyanidepulpwithionexchangerresin .Itavoidsliquidsolidseparation ,decreaseslossofgoldintailwashingsandincreasestherecoveryofgold[1,2 ] .353E…  相似文献   
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结合了当前造纸行业自动化的要求 ,介绍了纸浆配浆控制系统的设计与实现。系统具有功能强大、界面友好、调试容易、组态方便、运行稳定等优点  相似文献   
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The structural organization and fine distribution of the lymphatic networks in the periodontal tissues (gingiva, periodontal membrane, and alveolar process) and dental pulp of animals and humans were reviewed with special reference to histochemical examination by light and electron microscopy. The distinction between lymphatics and blood vessels was made on cryostat sections of undecalcified and calcified teeth treated with EDTA solution and whole mount preparations of periodontal membranes using 5'-nucleotidase (5'-Nase)-alkaline phosphatase (ALPase) double staining. This staining procedure allowed lymphatic vessels in the periodontal tissue and dental pulp to be differentiated from blood vessels. The specificity and localization of the enzyme reactions were confirmed by comparative histochemical studies of the same specimen with light microscopy and scanning or transmission electron microscopy. Well-developed 5'-Nase-positive lymphatic networks were observed on the tissue sections and whole mount preparations of the gingiva, periodontium, and dental pulp. More lymphatic vessels were seen in the root area of the periodontium than in the cervical area. In the dental pulp, lymphatic vessels were more numerous in the central part than in the peripheral odontoblastic layer. These distributions of the lymphatic capillary networks are discussed in relation to their ability to supply lymph to the teeth.  相似文献   
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This study investigates the co-digestion of poultry manure (PM) with sugar beet pulp residues (SBPR) obtained from saccharification and dewatering of sugar beet pulp. The laboratory-scale experiments were conducted under batch and semi-continuous conditions at mesophilic temperatures (35 °C). Batch tests gave specific biogas and methane yields of 590 dm3/kgVSfed and 423 dm3CH4/kgVSfed, respectively for SBPR, whereas the corresponding values for PM were 434 dm3/kgVSfed and 300 dm3CH4/kgVSfed. The co-digestion of PM with SBPR was found to increase biogas and methane yields compared to the manure alone. In semi-continuous reactor experiments, the highest methane yield of 346 dm3 CH4/kgVSfed was achieved for the mixture containing poultry manure with 50% SBPR (weight basis) and a solids retention time (SRT) of 20 days. However, when poultry manure was digested as a sole feedstock, the biogas production was inhibited by ammonia, whereas the co-digestion of PM with 25% SBPR was slightly affected by volatile fatty acids, which concentrations exceeded 4000 g/m3.  相似文献   
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This article presents a study of the effect of drying methods on dyeing capacity of widespread European flora dyestuff plant materials. The natural colorants, derived from the selected plant materials, were applied on chemical pulp in order to examine their dyeability. In this work, three different drying methods were examined—the natural, the air-, and the freeze-drying method—in various conditions. The plant materials that were dried naturally show weak dyeing results in comparison with the air- and freeze-dried materials. Freeze drying significantly improved the dyeing capacity of dyestuff plant materials with high initial moisture content. On the other hand, air drying at low temperature and high relative humidity improved the dyeing capacity of plant materials with low initial moisture content.  相似文献   
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In this study, carboxymethyl sago pulp (CMSP) derived from sago waste was successfully crosslinked with ferric ions in the presence of chitosan forming a novel immobilization matrix for p-nitrophenol (PNP)-acclimated activated sludge. On the basis of the shortest biodegradation time of PNP, the optimized operational conditions of immobilization were found to be: 7 w/v% CMSP, 9 g L−1 of activated sludge, 0.1 M ferric ion, and 15 min of crosslinking time. Observable inhibited PNP biodegradation was exhibited by the suspended activated sludge at the initial PNP concentration of 400 mg L−1. In contrast, complete mineralization was achieved by the CMSP/chitosan-immobilized activated sludge (CMSP/Ch-AS) beads. The results revealed the important role of CMSP/Ch hydrogel in protecting activated sludge from the toxicity of PNP. The CMSP/Ch-AS beads could be reused consecutively up to three and two cycles, respectively, for the biodegradation of PNP at 200 and 400 mg L−1, with the attainment of more than 99% of PNP removal at each cycle. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47531.  相似文献   
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Human dental pulp stem cells (hDPSCs) are some of the most promising stem cell types for regenerative therapies given their ability to grow in the absence of serum and their realistic possibility to be used in autologous grafts. In this review, we describe the particular advantages of hDPSCs for neuroregenerative cell therapies. We thoroughly discuss the knowledge about their embryonic origin and characteristics of their postnatal niche, as well as the current status of cell culture protocols to maximize their multilineage differentiation potential, highlighting some common issues when assessing neuronal differentiation fates of hDPSCs. We also review the recent progress on neuroprotective and immunomodulatory capacity of hDPSCs and their secreted extracellular vesicles, as well as their combination with scaffold materials to improve their functional integration on the injured central nervous system (CNS) and peripheral nervous system (PNS). Finally, we offer some perspectives on the current and possible future applications of hDPSCs in neuroregenerative cell therapies.  相似文献   
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