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Cultivation of aerobic granules for simultaneous nitrification and denitrification by seeding different inoculated sludge 被引量:5
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作者 WANGFang YANGFeng-lin LIUYi-hui ZHANGXing-wen 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2005年第2期268-270,共3页
Cultivation of aerobic granules for simultaneous nitrification and denitrification in two sequencing batch airlift bioreactors was studied. Conventional activated floc and anaerobic granules served as main two inocula... Cultivation of aerobic granules for simultaneous nitrification and denitrification in two sequencing batch airlift bioreactors was studied. Conventional activated floc and anaerobic granules served as main two inoculated sludge in the systems. Morphological variations of sludge in the reactors were observed. It was found that the cultivation of aerobic granules was closely associated with the kind of inoculated sludge. Round and regular aerobic granules were prevailed in both reactors, and the physical characteristics of the aerobic granules in terms of settling ability, specific gravity, and ratio of water containing were distinct when the inoculate sludge was different. Aerobic granules formed by seeding activated floc are more excellent in simultaneous nitrification and denitrification than that by aerobic granules formed from anaerobic granules. It was concluded that inoculated sludge plays a crucial role in the cultivation of aerobic granules for simultaneous nitrification and denitrification. 展开更多
关键词 aerobic granulation inoculated sludge NITRIFICATION DENITRIFICATION inner structure sludge morphology
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Comparison Study on Clinical and Neuropathological Characteristics of Hamsters Inoculated With Scrapie Strain 263K in Different Challenging Pathways 被引量:7
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作者 JINZHANG LANCHEN +10 位作者 BAO-YUNZHANG JUNHAN XIN-LIXIAO HAI-YANTIAN BIN-LINGLI CHENGAO JIAN-MEIGAO GUI-PINGMA CAI-MINXU YONGLIU XIAO-PINGDONG 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2004年第1期65-78,共14页
Objective To understand the infectious characteristics of a hamster-adapted scrapie strain 263K with five different routes of infection including intracerebral (i.e.), intraperitoneal (i.p.), intragastrical (i.g.), in... Objective To understand the infectious characteristics of a hamster-adapted scrapie strain 263K with five different routes of infection including intracerebral (i.e.), intraperitoneal (i.p.), intragastrical (i.g.), intracardiac and intramuscular (i.m.) approaches. Methods Hamsters were infected with crude- or fine-prepared brain extracts. The neuropathological changes, PrPSc deposits, and patterns of PK-resistant PrP were analyzed by HE stain, immunohistochemistry (IHC) assay and Western blot. Reactive gliosis and neuron loss were evaluated by glial fibrillary acidic protein (GFAP) and neuron specific enolase (NSE) specific IHC. Results The animals inoculated in i.m. and Lp. ways with crude PrPSc extracts showed clinical signs at the average incubation of 69.212.8 and 65.5±3.9 days. Inoculation in i.c. and intracardiac ways with fine PrPSc extracts (0.00035 g) caused similar, but relative long incubation of around 90 days. Only one out of eight hamsters challenged in i.g way with low dosage (0.01 g) became ill after a much longer incubation (185 d), while all animals (4/4) with high dosage (0.04 g) developed clinical signs 105 days postinfection. The most remarkable spongiform degeneration and PrPSc deposits were found in brain stem among the five challenge groups generally. The number of GFAP-positive astrocytes increased distinctly in brain stems in all infection groups, while the number of NSE-positive cells decreased significantly in cerebrum, except i.c. group. The patterns of PK-resistant PrP in brains were basically identical among the five infection routes. Conclusion Typical TSE could be induced in hamsters by inoculating strain 263K in the five infection ways. The incubation periods in bioassays depend on infective dosage, administrating pathway and preparation of PrPSc. The neuropathological changes and PrPSc deposits seem to be related with regions and inoculating pathways. 展开更多
关键词 Transmissible spongifonn encephalopathy SCRAPIE Strain 263K PrP^(Sc) Bioassay NEUROPATHOLOGY inoculating pathways
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Grain refinement of Mg-Al alloys inoculated by MgAl_(2)O_(4)powder 被引量:10
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作者 Hengbin Liao Meiyan Zhan +2 位作者 Chengbo Li Zhiqiang Ma Jun Du 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2021年第4期1215-1223,共9页
As a potent nucleating substrate forα-Mg grain,MgAl_(2)O_(4) powder was used to inoculate the Mg-Al melt in this study.The effects of MgAl_(2)O_(4)amount,holding time and Al content on the grain size and grain refini... As a potent nucleating substrate forα-Mg grain,MgAl_(2)O_(4) powder was used to inoculate the Mg-Al melt in this study.The effects of MgAl_(2)O_(4)amount,holding time and Al content on the grain size and grain refining ratio of the inoculated Mg-Al alloys are systematically investigated.The results show that the minimum grain size of Mg-3Al alloy is achieved by adding 2wt.%MgAl_(2)O_(4)powder and this alloy exhibits higher grain refining ratio than Mg-5Al and Mg-8Al alloys.The crystallographic misfit calculation indicates the wellmatching and possible orientation relationships(ORs)betweenα-Mg and MgAl_(2)O_(4).Among these predicted ORs,[10–10]α−Mg//[110]MgAl2O4 in(0002)α−Mg//(1–13)MgAl2O4 possesses the smallest misfit,i.e.,2.34%(fr).Both results of the experiment and crystallographic calculation demonstrate that the grain refinement of Mg-Al alloys is attributed to the MgAl_(2)O_(4)particles acting as the heterogeneous nucleation substrates forα-Mg grains. 展开更多
关键词 Grain refinement inoculation Heterogeneous nucleation Mg-Al alloys MgAl_(2)O_(4)
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Thermal analysis control of in-mould and ladle inoculated grey cast irons 被引量:4
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作者 Mihai Chisamera Iulian Riposan +2 位作者 Stelian Stan Eduard Stefan George Costache 《China Foundry》 SCIE CAS 2009年第2期145-151,共7页
The effect of addition of 0.05wt.% to 0.25 wt.% Ca,Zr,Al-FeSi alloy on in-ladle and in-mould inoculation of grey cast irons was investigated.In the present paper,the conclusions drawn are based on thermal analysis.For... The effect of addition of 0.05wt.% to 0.25 wt.% Ca,Zr,Al-FeSi alloy on in-ladle and in-mould inoculation of grey cast irons was investigated.In the present paper,the conclusions drawn are based on thermal analysis.For the solidification pattern,some specific cooling curves characteristics,such as the degree of undercooling at the beginning of eutectic solidif ication and at the end of solidifi cation,as well as the recalescence level,are identif ied to be more influenced by the inoculation technique.The degree of eutectic undercooling of the electrically melted base iron having 0.025% S,0.003% Al and 3.5% Ce is excessively high(39-40℃),generating a relatively high need for inoculation.Under these conditions,the in-mould inoculation has a more signif icant effect compared to ladle inoculation,especially at lower inoculant usage(less than 0.20 wt.%).Generally,the eff iciency of 0.05wt.% -0.15wt.% of alloy for in-mould inoculation is comparable to,or better than,that of 0.15wt.% -0.25wt.% addition in ladle inoculation procedures.In order to secure stable and controlled processes,representative thermal analysis parameters could be used,especially in thin wall grey iron castings production. 展开更多
关键词 接种技术 灰铸铁件 分析控制 钢包 模具 铝硅铁合金 共晶凝固 冷却曲线
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Effect of Morphology of Instantaneous Inoculant on Inoculated Result of Melted Iron
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作者 SHENG Da 《Journal of Iron and Steel Research(International)》 SCIE EI CAS CSCD 2003年第4期38-41,共4页
The characteristics of some elements in inoculant were analyzed.The effect of the morphology of instantaneous inoculant on its melting velocity was studied.When the inoculants pass through the same sieve number,the vo... The characteristics of some elements in inoculant were analyzed.The effect of the morphology of instantaneous inoculant on its melting velocity was studied.When the inoculants pass through the same sieve number,the volume and the ratio of surface area to volume are different.It is evident from the theoretical analysis and experiment under some conditions that the melting velocity of inoculant depends on the morphology of inoculant.The morphology of inoculant during production should be controlled carefully. 展开更多
关键词 instantaneous inoculant MORPHOLOGY melting velocity melted iron
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Ruminal degradability of Guinea grass silage inoculated with Streptoccocus bovis isolated from bovine rumen combined or not with com wheat bran
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作者 Emerson A. Bonelli Anderson de M. Zanine +2 位作者 Alexandre L. de Souza Daniele de J. Ferreira Guilherme R. Alves 《Agricultural Sciences》 2013年第12期628-634,共7页
This experiment aimed to evaluate the ruminal degradability in situ of the dry matter (DM), crude protein (CP), neutral detergent fiber (NDF) and acid detergent fiber (ADF) of Guinea grass silages. The experimental de... This experiment aimed to evaluate the ruminal degradability in situ of the dry matter (DM), crude protein (CP), neutral detergent fiber (NDF) and acid detergent fiber (ADF) of Guinea grass silages. The experimental design was completely randomized with six treatments and six repetitions: Guinea grass silage, Guinea grass silage inoculated with 10% wheat bran, Guinea grass silage inoculated with 106 cfu/g of strains of Streptococcus bovis JB1;Guinea grass silage inoculated with 106 cfu/g of strains of Streptococcus bovis JB1 plus 10% of wheat bran;Guinea grass silage inoculated with 106 cfu/g of strains of Streptococcus bovis HC5;Guinea grass silage inoculated with 106 cfu/g of strains of Streptococcus bovis HC5 plus 10% of wheat bran. The silages inoculated with Streptococcus bovis and with added wheat bran resulted in higher values of ruminal degradability of DM, 32.76% and 32.17%, and of crude protein 38.28% and 37.89%. For the effective and potential degradability of DM, CP, NDF and ADF the highest values occurred for silages in these silages as well, in all passage rates. There is a similarity between the responses of Streptococcus bovis JB1 and the HC5, and the wheat bran enhanced the effectiveness of the microbial additive. 展开更多
关键词 CRUDE Protein DIGESTION Dry MATTER Fiber inoculANT
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Strength Characteristics of Inoculated and Nodularised Thin Wall Ductile Iron Castings
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作者 Ezenwanyi Fidelia Ochulor Samson Oluropo Adeosun +1 位作者 Mohammed Olawale Hakeem Amuda Sanmbo Adewale Balogun 《Journal of Minerals and Materials Characterization and Engineering》 2015年第2期94-105,共12页
Carbide precipitates in Thin Wall Ductile Iron (TWDI) used for automotive applications needs to be eliminated or reduced for improved strength, ductility, crack propagation resistance and good machinability. Ductile i... Carbide precipitates in Thin Wall Ductile Iron (TWDI) used for automotive applications needs to be eliminated or reduced for improved strength, ductility, crack propagation resistance and good machinability. Ductile iron thin section profiles (≤3 mm) present danger of massive carbide precipitations in the as-cast sample. Precipitated carbide phase is brittle and negatively affects the mechanical properties of the iron matrix. The suppression of carbide formation is associated with the nucleating properties of the nodularizer and innoculant alloys. This treatment is vital in ensuring that carbide precipitation, flake graphite structure and non-nodular graphite phases are reduced or completely eliminated in the TWDI castings. Therefore, the temperature and technique of treatment would influence the yield of the process, and ultimately the mechanical properties. In this study, the effect of nodularization and inoculation treatment temperature on the microstructure and mechanical properties of TWDI castings is examined. The results indicate that good nodularity and nodule count with better percent elongations are achieved using low treatment temperatures in descending order of 1490°C, 1470°C and 1450°C, but have negative effect at lower treatment temperature of 1430°C. However, TWDI castings have superior properties in terms of nodule counts and nodularity at 1450°C. Treatment temperature does not produce significant influence on ultimate tensile strength (UTS) and hardness of TWDI castings. TWDI castings show poor nodularity, nodule count and ductility at higher inoculation treatment temperatures of 1550°C, 1530°C and 1510°C. 展开更多
关键词 THIN WALL DUCTILE IRON (TWDI) Nodularization inoculation GRAPHITE Structure
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Recorded Marked Changes in the Haematological and Immune Responses of Two Non-Transgenic Rodents Inoculated Orally and Intraperitoneally with <i>Trypanosoma brucei brucei</i>
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作者 O. N. Goselle S. S. Udoh +9 位作者 C. O. Ejete I. A. Iruobe S. Idoko A. D. Gyang Y. M. Ahmadu G. Y. Ajiji J. T. Sunday H. O. Awobode G. N. Imandeh B. M. Matur 《Advances in Infectious Diseases》 2020年第2期111-129,共19页
<strong>Objectives:</strong> The digestive track of mice and humans has always been an integral part of the pathogenesis of the Trypanosomes but is constantly overlooked. This realization opens up complete... <strong>Objectives:</strong> The digestive track of mice and humans has always been an integral part of the pathogenesis of the Trypanosomes but is constantly overlooked. This realization opens up completely new strategies for the development of trypanosomes vaccines, allowing approaches that parenteral delivery forms would not permit. The target of the study was to compare the haematological changes and immunological responses of trypanosomiasis model systems (mice and rats) inoculated orally and intraperitoneally and to observe the afterward effect of a controlled drug [Isometamidium chloride (ISM)] in the restoration of these initial parameters. <strong>Methods:</strong> To achieve this, a total of 40 rodents (20 rats and 20 mice) were purchased, then grouped into two [sixteen younger (1 - 5 weeks) and older (7 - 15 weeks) groups each]. They were further sub-grouped into five each. Body weights, Parasitaemia and Packed Cell Volume (PCV) were taken before, after inoculation and after treatment with ISM at 4 mg/kg. <strong>Results:</strong> Based on presumptive clinical diagnosis, all rodents inoculated intraperitoneally showed clinical signs of fluctuations in weight, PCV and parasitaemia levels before, after inoculations and after treatment compared to those inoculated orally with a significant difference (P < 0.05) observed. Both young and older rodents also responded differently to the inoculants and to the different methods of inoculation. But more deaths were recorded among the mice when compared to the rats. <strong>Conclusion: </strong>Although these non-transgenic models would not have offered a completely new methods to vaccine development, their differences in response to various methods of inoculations is an indication of an exciting research processes and could offer desired results, particularly where transgenic rodents are employed. 展开更多
关键词 Trypanosoma inoculation Non-Transgenic Rodents
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Seedling Petri-dish inoculation method:A robust,easy-to-use and reliable assay for studying plant-Ralstonia solanacearum interactions 被引量:1
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作者 CAO Peng CHEN Jia-lan +6 位作者 LI Ning-ning ZHANG Shuang-xi WANG Rong-bo LI Ben-jin LIU Pei-qing AN Yu-yan ZHANG Mei-xiang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第12期3709-3719,共11页
Ralstonia solanacearum causes a lethal bacterial wilt disease in many crops,leading to huge losses in crop production every year.Understanding of plant-R.solanacearum interactions will aid to develop efficient strateg... Ralstonia solanacearum causes a lethal bacterial wilt disease in many crops,leading to huge losses in crop production every year.Understanding of plant-R.solanacearum interactions will aid to develop efficient strategies to control the disease.As a soilborne pathogen,R.solanacearum naturally infects plants via roots.A huge limitation in studying plant-R.solanacearum interactions is the large variation of R.solanacearum infection assay due to the variable soil conditions and uneven inoculum exposure.Here,we developed a robust and reliable Petri-dish inoculation method which allows consistent and stable infection in young plant seedlings.This method is easy to use,takes about only 10 days from seed germination to the completion of inoculation assay,and requires less inoculum of bacteria as well as growth chamber space.We proved the efficacy of the seedling Petri-dish inoculation method by analyzing plant defense primed by molecular patterns,resistance of defense-related plant mutants,and virulence of R.solanacearum mutants.Furthermore,we demonstrated that the seedling Petri-dish inoculation method can be applied to other host plants such as tobacco and has great potential for high-throughput screening of resistant plant germplasms to bacterial wilt in the future. 展开更多
关键词 bacterial wilt Ralstonia solanacearum Petri-dish inoculation method VIRULENCE resistance defense priming
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Effect of Cu-Ni and Cu-Ni-Mn on the Microstructural and Mechanical Behaviour of As-Cast Non-Inoculated Hypereutectic Grey Iron
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作者 Seidu Ojo Adama Sumaila Onigbajumo Adetunji 《Journal of Minerals and Materials Characterization and Engineering》 2020年第2期27-46,共20页
The hypereutectic region of grey cast iron has received very little attention especially for designing cast products by researchers. Due to its high carbon equivalence, hypereutectic grey iron poses some challenges es... The hypereutectic region of grey cast iron has received very little attention especially for designing cast products by researchers. Due to its high carbon equivalence, hypereutectic grey iron poses some challenges especially its tendency for grey to white transition (GWT) at this level of carbon content. However, hypereutectic grey iron possesses inherent properties that could be easily utilized for improved performance in automobile engines and brake pad system. Significantly, they could be modified for superior hardness, strength and toughness. This study presents the effect of microalloying on the mechanical behaviour of hypereutectic grey cast iron with carbon equivalence above 4.5. The first part of this work presented in this paper considers the addition of Cu-Ni and Cu-Ni-Mn to series of as-cast hypereutectic grey cast iron and their hardness and tensile strength were studied and compared. A total of 33 cast samples were obtained with the control sample. The examination of the micrographs revealed that graphite eutectics cells of Type A and A + D were obtained in the resulting microstructure. Results analyses showed that the ferrite forming tendency of silicon was suppressed due to the high carbon content of the as-cast hypereutectic grey iron coupled with the absence of inoculation which plays a great role in the graphite flake type, network, size and distribution. Cu-Ni microalloying was also confirmed to promote hardness with the hardening effect limit of nickel observed at 1.3% composition. For Cu-Mi-Mn addition, excess and free sulphur in the hyper- eutectic grey iron results in reverse effect of manganese on strength, hardness, reduced graphite flake size and shape. 展开更多
关键词 HYPEREUTECTIC Grey IRON Microstructure Hardness Tensile Strength inoculation GRAPHITIZATION Cast IRON ALLOYING
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STUDY ON NUDE MICE INOCULATED WITH MYCOBACTERIUM LEPRAE BY MULTIPLE ROUTES
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作者 王荷英 张伟云 +2 位作者 喻林冲 施美琴 刘季和 《Chinese Medical Sciences Journal》 CAS CSCD 1995年第3期165-168,共4页
STUDYONNUDEMICEINOCULATEDWITHMYCOBACTERIUMLEPRAEBYMULTIPLEROUTESWangHeying(王荷英);ZhangWeiyun(张伟云);YuLinchong(... STUDYONNUDEMICEINOCULATEDWITHMYCOBACTERIUMLEPRAEBYMULTIPLEROUTESWangHeying(王荷英);ZhangWeiyun(张伟云);YuLinchong(喻林冲);ShiMeiqin(施美... 展开更多
关键词 麻风分支杆菌 免疫保护 动物实验 麻风结节损害
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Drought adaptation of Bauhinia faberi var.Microphylla seedlings with dual inoculation of arbuscular mycorrhizal fungi
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作者 LI Xia ZHU Wan-ze +3 位作者 WANG Wen-wu MA Sheng-lan SHENG Zhe-liang SHU Shu-miao 《Journal of Mountain Science》 SCIE CSCD 2023年第8期2214-2227,共14页
Bauhinia faberi via.Microphylla(BFM)is an important tree species for vegetation restoration in the dry valley of southwestern China.However,there were few studies on the application of arbuscular mycorrhizal fungi(AMF... Bauhinia faberi via.Microphylla(BFM)is an important tree species for vegetation restoration in the dry valley of southwestern China.However,there were few studies on the application of arbuscular mycorrhizal fungi(AMF)in improving the drought adaptation of BFM.In order to investigate the response of BFM to water stress(WS),we tested four inoculation treatments((no AMF,Control),Glomus mosseae(GM),Glomus intraradices(GI),Glomus mosseae+Glomus intraradices(GMI))in pots,experimented under three field water holding capacity(WHC)of 70%,50%and 30%.The changes of seedling survival rate(SR),AMF relative root length colonization rate(Col),growth,photosynthetic parameters,water status and leaf nutrients were examined.The results showed that under 30%WHC drought conditions,SR with dual inoculation of AMF was not higher than with single inoculation of GM,suggesting that increasing the diversity of AMF did not definitely improve plant SR,and that the species of inoculated AMF might have an important impact on SR.The sensitivity of dual inoculated Col to water stress was lower than that of single inoculation,which was more favorable for dual inoculated BFM seedlings adapting to drought environment.The overall drought resistance ability(D)also showed that dual inoculation of AMF improved plant drought adaptation compared with single inoculation,which was related to the higher Col of dual inoculated AMF.This study is of practical importance to promote vegetation restoration in arid areas in a cost-effective and environmentally friendly manner. 展开更多
关键词 Glomus mosseae Glomus intraradices Bauhinia faberi via.Microphylla Water stress Dual inoculation
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健康谣言的干预策略:基于信息生命周期的视角 被引量:2
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作者 吕小康 刘欣 +1 位作者 杨婷婷 付春野 《心理科学进展》 CSCD 北大核心 2024年第4期664-676,共13页
如何有效治理健康谣言是社交媒体时代的一大难题。健康谣言传播具有信息和信息加工主体两个层面的驱动因素,可依据信息生命周期理论将其分为产生期、评价期和传播期三阶段,系统归纳与分析不同阶段的健康谣言干预策略:产生期重在预防,强... 如何有效治理健康谣言是社交媒体时代的一大难题。健康谣言传播具有信息和信息加工主体两个层面的驱动因素,可依据信息生命周期理论将其分为产生期、评价期和传播期三阶段,系统归纳与分析不同阶段的健康谣言干预策略:产生期重在预防,强调对大众进行心理接种、提升自身健康素养;评价期关注个体的主观能动性,包括聚焦信息准确性以及促进自身分析式加工;传播期通过提高辟谣信息可信度、善用反驳文本和调节个体情绪状态,实现精准辟谣。未来研究可继续创新信息生命周期视角下健康谣言的治理策略,细化考察不同类型与易感人群下的干预手段;归纳与验证不同策略在现实世界中的应用效果,充分发挥行为科学与网络平台对建立健康谣言干预的长效机制的作用。 展开更多
关键词 健康谣言 错误信息 网络谣言 心理接种 真相三明治
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近代来华传教士雒魏林对《种痘法》的翻译及原因分析
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作者 李计筹 郭强 《医学与哲学》 北大核心 2024年第8期74-77,共4页
《种痘法》是中国人痘术理论技术经验的结晶,被多位近代来华传教士翻译成英文传至西方,尤其以雒魏林的译本最为完整,虽然其译本存在错译、漏译现象,但对该书完整地传至西方贡献很大。雒魏林翻译该书的原因有三:一是中医对天花的病因病... 《种痘法》是中国人痘术理论技术经验的结晶,被多位近代来华传教士翻译成英文传至西方,尤其以雒魏林的译本最为完整,虽然其译本存在错译、漏译现象,但对该书完整地传至西方贡献很大。雒魏林翻译该书的原因有三:一是中医对天花的病因病机认识深刻且治疗规范成熟;二是部分种痘法则契合现代西医理念;三是希望通过种痘慈善活动开拓医疗传教事业。《种痘法》是19世纪初来华新教传教士翻译的中医著作的代表,反映了在近代西医东渐过程中,中医并非只是单一受西方医学影响的对象,某些传统中医的理论和技术同样具有超前性和现代性,对当时世界医学的发展做出了重要贡献。 展开更多
关键词 《种痘法》 天花 人痘术 传教士 翻译
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减施氮肥和接种根瘤菌对大豆生理生长与氮素利用效率及产量的影响
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作者 向友珍 张威 +3 位作者 唐子竣 付骏宇 李志军 张富仓 《农业机械学报》 EI CAS CSCD 北大核心 2024年第3期340-351,共12页
在干旱、半干旱地区农业生产中,广泛采用接种根瘤菌、施用氮素等措施来促进大豆生长以提高产量,然而少有研究讨论接种根瘤菌与施用氮素的交互作用对大豆生长和产量的影响规律。本研究通过为期2年的田间试验,设置4个施氮水平(N0:0 kg/hm^... 在干旱、半干旱地区农业生产中,广泛采用接种根瘤菌、施用氮素等措施来促进大豆生长以提高产量,然而少有研究讨论接种根瘤菌与施用氮素的交互作用对大豆生长和产量的影响规律。本研究通过为期2年的田间试验,设置4个施氮水平(N0:0 kg/hm^(2);N1:60 kg/hm^(2);N2:120 kg/hm^(2);N3:180 kg/hm^(2))和2种接种水平,即接种根瘤菌(R)和清水拌种。在大豆各生育期测量根瘤数、根瘤干质量、叶面积指数、干物质积累及根系特性等大豆生长指标和叶绿素含量、光合参数、荧光参数等生理指标,同时还测定氮素吸收量等指标并计算氮素利用效率。结果表明,RN2处理下的大豆生长状况最佳,2年平均最大根瘤数为241.47、最大根瘤干质量为1.30 g、最大根长密度为15.00 cm/cm^(3)、最大叶面积指数为5.44 cm^(2)/cm^(2)、最大干物质积累量为17 530.51 kg/hm^(2)、最大叶绿素含量为53.55、最大净光合速率为32.75μmol/(m^(2)·s)、最大种子产量为4 659.4 kg/hm^(2)。由此可见减少氮肥施用量(N2)的同时接种根瘤菌(R)对于促进关中平原大豆的生理生长、提升对氮素的利用效率、提高大豆产量具有重要意义。本研究可为提高干旱半干旱地区大豆生产水平提供理论支持和实践经验。 展开更多
关键词 大豆 施氮 接种根瘤菌 氮肥利用效率 产量
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不同孕育剂随流孕育对微合金化球墨铸铁组织和性能的影响
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作者 李蒙 任莎歌 +1 位作者 李贵胜 祝庆 《兵器材料科学与工程》 CAS CSCD 北大核心 2024年第2期77-83,共7页
为探究硫氧孕育剂随流孕育对微合金化球墨铸铁组织和性能的影响,在相同铸造条件下,用树脂砂型分别浇注75Si Fe孕育剂和硫氧孕育剂随流孕育处理的球墨铸铁试样。通过组织观察、室温拉伸试验、布氏硬度试验等分析了两种不同孕育剂随流孕... 为探究硫氧孕育剂随流孕育对微合金化球墨铸铁组织和性能的影响,在相同铸造条件下,用树脂砂型分别浇注75Si Fe孕育剂和硫氧孕育剂随流孕育处理的球墨铸铁试样。通过组织观察、室温拉伸试验、布氏硬度试验等分析了两种不同孕育剂随流孕育对微合金化球墨铸铁的显微组织、力学性能和拉伸断口的影响,探寻硫氧孕育剂随流孕育与球墨铸铁组织和性能的联系。结果表明:两种试样均由大量的珠光体、少量的铁素体、大量的石墨球组成,其中用75Si Fe孕育剂进行随流孕育,石墨球易畸变,圆整度不好,石墨球数量少,尺寸较大,平均球化率为84%,平均石墨球数为137个/mm^(2);而用硫氧孕育剂进行随流孕育,石墨形态改善明显,石墨球径更细小,分布更均匀,石墨球数量大幅增加,平均球化率为91%,平均石墨球数为297个/mm^(2)。硫氧孕育剂试样的抗拉强度和断后伸长率均高于75Si Fe孕育剂,分别为874 MPa和6.4%。硫氧孕育剂随流孕育球墨铸铁试样断裂模式为伴有少量塑性变形的准解理断裂。综合认为,用硫氧孕育剂随流孕育可获得较高的综合力学性能。 展开更多
关键词 微合金化球墨铸铁 硫氧孕育剂 随流孕育 显微组织 力学性能
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新冠病毒疫苗接种对肺功能的保护作用及早期新冠肺炎的影响
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作者 许诺 沈志文 +2 位作者 杨燕平 陈智鸿 李丽 《复旦学报(医学版)》 CAS CSCD 北大核心 2024年第4期574-579,593,共7页
目的探讨新冠病毒疫苗接种对新冠病毒感染患者肺功能的影响以及新冠病毒疫苗接种对感染患者的保护作用。方法选取2023年1月7日至2023年2月7日期间在复旦大学附属中山医院完成肺功能检查的1178例门诊及住院新冠感染患者,按照是否患有新... 目的探讨新冠病毒疫苗接种对新冠病毒感染患者肺功能的影响以及新冠病毒疫苗接种对感染患者的保护作用。方法选取2023年1月7日至2023年2月7日期间在复旦大学附属中山医院完成肺功能检查的1178例门诊及住院新冠感染患者,按照是否患有新冠肺炎分为两组,完成“新冠感染症状及肺功能相关调查表”,同时采集患者疫苗接种情况、临床症状、肺通气功能、弥散功能和呼出气一氧化氮结果(fractional exhaled nitric oxide,FeNO)等临床资料,通过χ^(2)检验、Pearson相关性分析、单因素及多因素Logistic回归模型等方法分析接种和未接种新冠病毒疫苗患者肺功能的差异,并验证新冠病毒疫苗对新冠肺炎、新冠感染相关症状的保护作用。结果未接种新冠病毒疫苗的新冠感染患者通气及弥散肺功能较接种患者下降明显(P<0.05)。未接种过新冠病毒疫苗、有既往慢性病史的患者更容易发生新冠肺炎,二针/三针疫苗接种可以减少新冠肺炎的发生率(P<0.05),而接种一针无明显保护作用;既往慢性病病史患者,如发生新冠感染,容易出现严重症状,而接种新冠病毒疫苗可以减轻包括慢性病患者在内的新冠相关严重症状。结论新冠病毒感染可以造成患者肺通气及弥散功能下降,二针/三针新冠病毒疫苗的接种可能减轻新冠病毒感染对肺功能的损伤,减少新冠肺炎及严重症状的发生,完整的新冠病毒疫苗接种可能具有保护作用。 展开更多
关键词 新型冠状病毒肺炎(COVID-19) 疫苗接种 肺功能
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葡萄干酿制葡萄酒的工艺优化
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作者 林范学 韩小龙 +1 位作者 师艳秋 来庆华 《食品安全质量检测学报》 CAS 2024年第4期203-209,共7页
目的研究并优化用普通葡萄干酿造葡萄酒的工艺。方法通过单因素和正交试验研究料水比、果胶酶添加量、酵母菌接种量和发酵温度对葡萄酒品质的影响,并优化酿造工艺。结果单因素试验结果表明,料水比、果胶酶的添加量以及发酵温度主要影响... 目的研究并优化用普通葡萄干酿造葡萄酒的工艺。方法通过单因素和正交试验研究料水比、果胶酶添加量、酵母菌接种量和发酵温度对葡萄酒品质的影响,并优化酿造工艺。结果单因素试验结果表明,料水比、果胶酶的添加量以及发酵温度主要影响葡萄酒的色度,对残糖浓度和酒精度的影响不明显。相比之下,酵母菌接种量对这些特性的改变贡献较小。正交试验表明,发酵温度、酵母菌接种量和料水比对酒精度有显著影响,且果胶酶添加量明显影响感官评分。在最佳的发酵条件下[发酵温度20℃、酵母菌接种量0.50 g/L、果胶酶的添加量25 mg/L、料水比1:6(g/mL)],可以酿造出酒精度约为12.3%vol,感官评分约为90.5分的高品质葡萄酒。结论普通葡萄干酿制葡萄酒可行性较高,不同因素组合选择余地大,葡萄酒品质符合国家标准,酿造工艺具有一定的商业价值。 展开更多
关键词 葡萄干 料水比 果胶酶 接种量 发酵温度 工艺优化
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植物乳杆菌和模仿葡萄球菌复配对发酵羊肉香肠理化性质、风味及多肽抗氧化能力的影响
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作者 冯美琴 龚瑶 孙健 《食品科学》 EI CAS CSCD 北大核心 2024年第12期116-124,共9页
本研究以植物乳杆菌(Lactobacillus plantarum)CD101和模仿葡萄球菌(Staphylococcus simulans)NJ201作为复配发酵剂制作发酵羊肉香肠,以不接菌自然发酵香肠为空白对照。通过测定两组pH值、色差、质构等理化指标,游离氨基酸、挥发性风味... 本研究以植物乳杆菌(Lactobacillus plantarum)CD101和模仿葡萄球菌(Staphylococcus simulans)NJ201作为复配发酵剂制作发酵羊肉香肠,以不接菌自然发酵香肠为空白对照。通过测定两组pH值、色差、质构等理化指标,游离氨基酸、挥发性风味物质的种类与含量,测定从香肠中提取的多肽对1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picrylhydrazyl,DPPH)自由基、2,2’-联氮双(3-乙基苯并噻唑啉-6-磺酸)(2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid),ABTS)阳离子自由基、羟自由基的清除能力,探究复配发酵剂对发酵羊肉香肠理化性质、风味及多肽抗氧化能力的改善作用。结果表明,植物乳杆菌CD101和模仿葡萄球菌NJ201复配发酵能够迅速降低羊肉香肠在发酵期间的pH值,提高香肠的安全性;提高羊肉香肠的亮度与色泽、硬度和咀嚼性,改善其品质;增加游离氨基酸总量、挥发性风味物质种类,提升羊肉香肠的风味;显著提高羊肉香肠多肽对DPPH自由基、ABTS阳离子自由基以及羟自由基的清除率,提升香肠多肽抗氧化活性。综上,接种发酵能对发酵羊肉香肠理化性质、风味及多肽的抗氧化能力均有明显改善。本研究能够为发酵肉制品的工业化生产提供理论依据。 展开更多
关键词 接种发酵 发酵羊肉香肠 理化性质 挥发性风味物质 抗氧化能力
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应用冠突散囊菌人工接种发酵不同种类茶叶的研究
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作者 孙玉姣 高润凝 +2 位作者 袁旭霜 罗昭君 胡一纯 《陕西科技大学学报》 北大核心 2024年第2期41-52,共12页
冠突散囊菌(Aspergillus cristatus)是茯砖茶发花过程中的优势菌群,其代谢产物具有良好的抗炎、抑菌、降脂和抗氧化活性等.采用真菌分离纯化技术从陕西茯砖茶中获得一株A.cristatus,将黑毛茶、乌龙茶、黄茶、绿茶、红茶和白茶六种茶叶... 冠突散囊菌(Aspergillus cristatus)是茯砖茶发花过程中的优势菌群,其代谢产物具有良好的抗炎、抑菌、降脂和抗氧化活性等.采用真菌分离纯化技术从陕西茯砖茶中获得一株A.cristatus,将黑毛茶、乌龙茶、黄茶、绿茶、红茶和白茶六种茶叶作为发酵基质进行人工接种发酵,研究发现经发酵后六种茶的可溶性糖、可溶性蛋白、总多酚、总黄酮和游离氨基酸含量均显著性降低;鼠李糖、阿拉伯糖、木糖、甘露糖、葡萄糖和半乳糖等六种单糖含量均显著性增加;其中黑毛茶、绿茶和白茶发酵后拥有更好的抗氧化活性.该研究结果可为冠突散囊菌的开发利用提供技术支撑. 展开更多
关键词 冠突散囊菌 人工接种 抗氧化活性
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