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991.
两种微生物菌种对园林废弃物高温堆肥影响的研究   总被引:1,自引:0,他引:1  
以园林废弃物为主要原料,采用高温好氧堆肥工艺,研究了园林废弃物堆肥体系中加入两种微生物菌剂(大华酵素菌速腐剂、金葵子腐杆剂)后温度、物理、化学性质的变化及其对园林废弃物堆肥品质的影响。结果表明,两种微生物菌剂中大华酵素菌对园林废弃物高温腐熟效果较优。添加微生物菌剂的堆肥处理都在堆肥3d后进入高温分解阶段,其中大华酵素菌的堆肥处理温度提高快,温度高且持续时间长,高温(65℃)持续时间可达10d。添加大华酵素菌的处理,腐熟后粒径较小,总养分高于金葵籽腐杆剂,改善了堆肥产品的品质。  相似文献   
992.
本文详细介绍了DPT系列双电源自动切换装置的工作原理、操作性能、保护性能进行了详细介绍,对电气接线及主要接点做了充分说明,并结合我厂实际应用效果进行了讲解,阐述该装置是值得推广和应用的。  相似文献   
993.
994.
We identified and characterized the TcLgl gene putatively encoding lethal giant larvae (Lgl) protein from the red flour beetle (Tribolium castaneum). Analyses of developmental stage and tissue-specific expression patterns revealed that TcLgl was constitutively expressed. To examine the role of TcLgl in insect development, RNA interference was performed in early (1-day) larvae, late (20-day) larvae, and early (1-day) pupae. The early larvae injected with double-stranded RNA of TcLgl (dsTcLgl) at 100, 200, and 400 ng/larva failed to pupate, and 100% mortality was achieved within 20 days after the injection or before the pupation. The late larvae injected with dsTcLgl at these doses reduced the pupation rates to only 50.3%, 36.0%, and 18.2%, respectively. The un-pupated larvae gradually died after one week, and visually unaffected pupae failed to emerge into adults and died during the pupal stage. Similarly, when early pupae were injected with dsTcLgl at these doses, the normal eclosion rates were reduced to only 22.5%, 18.0%, and 11.2%, respectively, on day 7 after the injection, and all the adults with abnormal eclosion died in two days after the eclosion. These results indicate that TcLgl plays an essential role in insect development, especially during their metamorphosis.  相似文献   
995.
996.
997.
建立了一种同时测定水样中乙二醇和甲醛含量的方法。采用品红-亚硫酸分光光度法,以乙二醇为标样,乙二醇含量在0.4~2.0μg/mL的范围内线性关系较好,R=0.998 9,检出限为0.2μg/mL,平均回收率99.72%。该方法简便、可靠,可作为水样中乙二醇和甲醛的含量测定方法。  相似文献   
998.
The thermal diffusion coefficient of the intumescent insulating layer, which forms when a fire-retardant coating is subjected to heat in a fire, is a key factor used in assessing the fire protection performance of the coating. However, because there are many factors influencing this coefficient, it is usually difficult to measure its value directly from tests. Based on the insulation failure experiment of a cable exposed to heat, the relationship between failure time, equivalent thermal diffusion coefficient, and thickness of expansion layer has been determined by means of numerical calculation from a heat transfer model built in this paper; a computing formula has been thus established. According to the formula, the equivalent thermal diffusion coefficient of the expansion layer can be determined after the diffusion coefficient and the thickness of the expansion layer are obtained from the insulation failure experiment of a cable.  相似文献   
999.
In the current study, the lipid-shell and polymer-core hybrid nanoparticles (lpNPs) modified by Arg–Gly–Asp(RGD) peptide, loaded with curcumin (Cur), were developed by emulsification-solvent volatilization method. The RGD-modified hybrid nanoparticles (RGD–lpNPs) could overcome the poor water solubility of Cur to meet the requirement of intravenous administration and tumor active targeting. The obtained optimal RGD-lpNPs, composed of PLGA (poly(lactic-co-glycolic acid))–mPEG (methoxyl poly(ethylene- glycol)), RGD–polyethylene glycol (PEG)–cholesterol (Chol) copolymers and lipids, had good entrapment efficiency, submicron size and negatively neutral surface charge. The core-shell structure of RGD–lpNPs was verified by TEM. Cytotoxicity analysis demonstrated that the RGD–lpNPs encapsulated Cur retained potent anti-tumor effects. Flow cytometry analysis revealed the cellular uptake of Cur encapsulated in the RGD–lpNPs was increased for human umbilical vein endothelial cells (HUVEC). Furthermore, Cur loaded RGD–lpNPs were more effective in inhibiting tumor growth in a subcutaneous B16 melanoma tumor model. The results of immunofluorescent and immunohistochemical studies by Cur loaded RGD–lpNPs therapies indicated that more apoptotic cells, fewer microvessels, and fewer proliferation-positive cells were observed. In conclusion, RGD–lpNPs encapsulating Cur were developed with enhanced anti-tumor activity in melanoma, and Cur loaded RGD–lpNPs represent an excellent tumor targeted formulation of Cur which might be an attractive candidate for cancer therapy.  相似文献   
1000.
MicroRNAs (miRNAs) have essential roles in carcinogenesis and tumor progression. Here, we investigated the roles and mechanisms of miR-143 in non-small cell lung cancer (NSCLC). miR-143 was significantly decreased in NSCLC tissues and cell lines. Overexpression of miR-143 suppressed NSCLC cell proliferation, induced apoptosis, and inhibited migration and invasion in vitro. Integrated analysis identified LIM domain kinase 1 (Limk1) as a direct and functional target of miR-143. Overexpression of Limk1 attenuated the tumor suppressive effects of miR-143 in NSCLC cells. Moreover, miR-143 was inversely correlated with Limk1 expression in NSCLC tissues. Together, our results highlight the significance of miR-143 and Limk1 in the development and progression of NSCLC.  相似文献   
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