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浮胶引起的缺陷对CCD成像的影响分析
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作者 龙飞 张故万 +2 位作者 吴可 廖乃鏝 李仁豪 《半导体光电》 CAS CSCD 北大核心 2013年第4期554-559,共6页
针对大面阵CCD成像黑缺陷多的特点,从机理和制作工艺上进行了分析研究。结果表明,CCD成像黑缺陷主要由光刻工艺缺陷引起。光刻LOCOS、地和沟阻工艺中产生的浮胶是CCD成像黑缺陷的主要来源。在制作多晶硅栅过程中,光刻浮胶可产生成像黑... 针对大面阵CCD成像黑缺陷多的特点,从机理和制作工艺上进行了分析研究。结果表明,CCD成像黑缺陷主要由光刻工艺缺陷引起。光刻LOCOS、地和沟阻工艺中产生的浮胶是CCD成像黑缺陷的主要来源。在制作多晶硅栅过程中,光刻浮胶可产生成像黑缺陷或导致信号电荷转移问题。最后,提出了减少光刻工艺产生浮胶的方法。 展开更多
关键词 CCD 光刻 浮胶 缺陷
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美浮特皮肤抗菌液联合美浮特滋润修护凝胶治疗窝状角质松解症的临床研究
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作者 季雅娟 《中国社区医师》 2022年第8期13-15,共3页
目的:观察美浮特皮肤抗菌液联合美浮特滋润修护凝胶治疗窝状角质松解症的临床疗效。方法:选取2019-2021年在北京市昌平区中西医结合医院皮肤科门诊就诊和招募的窝状角质松解症病例24例,随机分成两组。治疗组采用美浮特皮肤抗菌液局部浸... 目的:观察美浮特皮肤抗菌液联合美浮特滋润修护凝胶治疗窝状角质松解症的临床疗效。方法:选取2019-2021年在北京市昌平区中西医结合医院皮肤科门诊就诊和招募的窝状角质松解症病例24例,随机分成两组。治疗组采用美浮特皮肤抗菌液局部浸泡,联合美浮特滋润修护凝胶涂抹。对照组采用中药汤剂浸泡治疗。治疗时长8周。然后评估皮损变化及治疗效果,治疗结束后6个月进行随访。结果:治疗组12例,治愈10例,好转1例,无效1例,治愈率83.3%(10/12),有效率91.6%(11/12)。2例(16.7%)患者初期用药后局部皮肤出现红肿疼痛,经过对症治疗后症状缓解,未影响后续治疗。治疗过程中患者均无全身不良反应。对照组12例,治愈2例,好转2例,无效8例,治愈率16.6%(2/12),有效率33.3%(4/12)。治疗组的治愈率及有效率均明显优于对照组,差异有统计学意义(P<0.05)。结论:美浮特皮肤抗菌液联合美浮特滋润修护凝胶治疗窝状角质松解症的临床疗效优势显著,可操作性强,安全性好,值得临床推广使用。 展开更多
关键词 窝状角质松解症 特皮肤抗菌液 特滋润修护凝
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美浮特皮肤抗菌液联合皮肤抗菌凝胶治疗多发性跖疣40例疗效观察 被引量:2
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作者 尹建凯 徐畅 +2 位作者 袁公 吴丽娟 尹建玲 《皮肤病与性病》 2020年第6期892-894,共3页
目的观察美浮特皮肤抗菌液联合皮肤抗菌凝胶治疗多发性跖疣的临床疗效。方法选择皮肤科门诊确诊的多发性跖疣病例40例,采用美浮特皮肤抗菌液联合皮肤抗菌凝胶局部浸泡、封包,治疗(4~8)周,观察疣体脱落情况,评估病情变化及治疗效果,随访... 目的观察美浮特皮肤抗菌液联合皮肤抗菌凝胶治疗多发性跖疣的临床疗效。方法选择皮肤科门诊确诊的多发性跖疣病例40例,采用美浮特皮肤抗菌液联合皮肤抗菌凝胶局部浸泡、封包,治疗(4~8)周,观察疣体脱落情况,评估病情变化及治疗效果,随访6个月,观察复发情况。结果 40例患者治愈35例,显效3例,好转1例,无效1例。治愈率为87.5%(35/40),有效率为95.0%(38/40)。9例(22.5%)患者用药后局部出现轻微疼痛、红肿,对症治疗后症状缓解,未影响完整疗程,无全身不良反应。结论美浮特皮肤抗菌液联合使用美浮特皮肤抗菌凝胶治疗多发性跖疣的临床疗效显著,方法简单,复发率低,安全性好,值得临床应用。 展开更多
关键词 多发性跖疣 特皮肤抗菌液 特皮肤抗菌凝 疗效
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桃红清血丸、卡介菌多糖核酸联合皮肤抗菌凝胶治疗面部扁平疣的临床观察
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作者 马成龙 尚颖 +2 位作者 马玉霞 马忠国 何菊花 《中文科技期刊数据库(引文版)医药卫生》 2022年第9期142-145,共4页
评价卡介菌多糖核酸注射液与皮肤抗菌凝胶相结合,治疗面部扁平疣的临床疗效。方法 由60例面部扁平疣的病患随机分配成研究组(23例)和对比组(21例)。桃红清血丸,早晚2次饭后半小时温服。研究组采取卡介菌多糖核酸注射液与皮肤抗菌凝胶进... 评价卡介菌多糖核酸注射液与皮肤抗菌凝胶相结合,治疗面部扁平疣的临床疗效。方法 由60例面部扁平疣的病患随机分配成研究组(23例)和对比组(21例)。桃红清血丸,早晚2次饭后半小时温服。研究组采取卡介菌多糖核酸注射液与皮肤抗菌凝胶进行治疗,对比组采取卡介菌多糖核酸注射液与重组人干扰素α-2b 乳膏进行治疗。两组连续使用8周。结果 研究组和对比组的治愈率分别为82.60%和52.37%,差异有统计学意义(P<0. 05);有效率则分别为91.30%和76.19%,差异无统计学意义(P>0. 05)。结论 卡介菌多糖核酸联合皮肤抗菌凝胶治疗面部扁平疣的临床疗效显著,且使用简便安全,值得在基层医疗机构推广应用。 展开更多
关键词 扁平疣 卡介菌多糖核酸 特皮肤抗菌凝 重组人干扰素Α-2B 乳膏
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集成光学制备工艺中的清洗和腐蚀
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作者 郭亚明 《半导体技术》 CAS CSCD 北大核心 2005年第1期32-34,共3页
论述了集成光学光刻、镀膜工艺中对基片的清洗步骤,阐述了常规材料的腐蚀方法及腐蚀液配制,并分析了腐蚀工艺过程中易出现的问题。
关键词 超声波清洗 干法/湿法腐蚀 浮胶 晶片再生
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Separation behavior and mechanism of hematite and collophane in the presence of collector RFP-138 被引量:1
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作者 余侃萍 余永富 许向阳 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第2期501-507,共7页
The reverse flotation separation performance and mechanism of hematite and cellophane in the presence of RFP-138, a newly synthesized dephosphorization collector, were studied. Reverse flotation tests on monominerals ... The reverse flotation separation performance and mechanism of hematite and cellophane in the presence of RFP-138, a newly synthesized dephosphorization collector, were studied. Reverse flotation tests on monominerals and artificially mixed minerals of hematite and collophanite show that, this anionic collector performs excellently in reducing the phosphorus content in hematite. It can decrease the content of P in artificially mixed minerals from 1.05% to 0.12% and achieve the TFe recovery rate of 91.30%. The chemical behavior of solution and infrared spectra of RFP-138 were investigated to explore the selective collecting mechanism of RFP-138 to these two minerals. 展开更多
关键词 HEMATITE collophane reverse flotation separation DEPHOSPHORIZATION dephosphorization collector
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优化腐槽工艺、提高表面钝化膜质量从而提高产品生产率
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作者 孙海萍 《黑龙江科技信息》 2008年第30期31-31,共1页
随着航天、航空等国家重点工程对军用电子元器件质量可靠性的保证要求的不断提高,我厂为求得企业的生存与发展,全厂各部门都在技术更新,其中我厂在腐槽工艺上存在着一些问题,为改善这一现状,我选择"优化腐槽工艺、提高表面钝化膜... 随着航天、航空等国家重点工程对军用电子元器件质量可靠性的保证要求的不断提高,我厂为求得企业的生存与发展,全厂各部门都在技术更新,其中我厂在腐槽工艺上存在着一些问题,为改善这一现状,我选择"优化腐槽工艺、提高表面钝化膜质量从而提高产品生产率"为论文研究内容。 展开更多
关键词 腐槽 玻璃钝化 工程能力指数 浮胶
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Dynamics of Dimethylsulfide and Dimethylsulfoniopropionate Produced by Phytoplankton in the Chinese Seas - Distribution Patterns and Affecting Factors 被引量:5
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作者 焦念志 柳成章 +3 位作者 洪华生 原田茂树 越川海 渡边正孝 《Acta Botanica Sinica》 CSCD 2003年第7期774-786,共13页
Distribution of dimethylsulfide (DMS) and/or particulate dimethylsulfoniopropionate (DMSPp) concentrations in the Jiaozhou Bay, Zhifu Bay and East China Sea were investigated during the period of 1994 - 1998. Both DMS... Distribution of dimethylsulfide (DMS) and/or particulate dimethylsulfoniopropionate (DMSPp) concentrations in the Jiaozhou Bay, Zhifu Bay and East China Sea were investigated during the period of 1994 - 1998. Both DMS and DMSPp levels showed remarkable temporal and spatial variations. High values occurred in the coastal or shelf waters and low values in the offshore waters. The highest levels were observed in spring or summer and lowest in autumn. DMS or DMSPp distribution patterns were associated with water mass on a large geographical scale, while biological and chemical factors were more likely influential on smaller-scale variations. Diatoms could play an important role in total DMS or DMSPp abundance in coastal waters. Nitrate was found to have a two-phase relationship with DMSPp concentrations: positive when nitrate concentration was lower than 1 mumol/L, and negative when it was above. Anthropogenic factors such as sewage input and aquaculture also showed influences on DMS or DMSPp concentration. 展开更多
关键词 dimethylsulfide (DMS) particulate dimethylsulfoniopropionate (DMSPp) nitrogen DIATOMS Chinese seas
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Examination of Daytime Length's Influence on Phytoplankton Growth in Jiaozhou Bay, China 被引量:12
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作者 杨东方 高振会 +2 位作者 张经 崔文林 石强 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2004年第1期70-82,共13页
This study showed how the daytime length in Jiaozhou Bay affected the water temperature, which in turn affected the phytoplankton growth when solar radiation was sufficient for phytoplankton photosynthesis. Jiaozhou B... This study showed how the daytime length in Jiaozhou Bay affected the water temperature, which in turn affected the phytoplankton growth when solar radiation was sufficient for phytoplankton photosynthesis. Jiaozhou Bay observation data collected from May 1991 to February 1994 were used to analyze the daytime length vs water temperature relationship. Our study showed that daytime length and the variation controlled the cycle of water temperature flunctuation. Should the cyclic variation curve of the daytime length be moved back for two months it would be superimposed with temperature change. The values of daytime length and temperature that calculated in the dynamical model of daytime length lag vs water temperature were consistent with observed values. The light radiation and daytime length in this model determined the photochemistry process and the enzymic catalysis process of phytoplankton photosynthesis. In addition, by considering the effect of the daytime length on water temperature and photosynthesis, we could comprehend the joint effect of daytime length, water temperature, and nutrients, on the spatiotemporal variation of primary production in Jiaozhou Bay. 展开更多
关键词 daytime length water temperature primary production Jiaozhou Bay
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Silicon limitation on primary production and its destiny in Jiaozhou Bay, China VI: The ecological variation process of the phytoplankton 被引量:9
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作者 杨东方 高振会 +2 位作者 孙培艳 赵升 张友篪 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2006年第2期186-203,共18页
The combination effect of light, water temperature and nutrients on phytoplankton growth in Jiaozhou Bay is studied in this paper. The order of importance of the influence on phytoplankton growth is de- termined as nu... The combination effect of light, water temperature and nutrients on phytoplankton growth in Jiaozhou Bay is studied in this paper. The order of importance of the influence on phytoplankton growth is de- termined as nutrients, water temperature, and light. The influence of these factors unveiled the mechanism of the influence, and revealed the variation process of the nutrients limiting phytoplankton primary production, and of the water temperature influencing the phytoplankton reproduction capacity, and hence influencing the structure of phytoplankton assemblage. Temporal and spatial quantification shows different stages of the influence by wa- ter temperature and nutrients on the phytoplankton growth. Moreover, the authors expatiated the ideal state of the phytoplankton growth and the reason of red tide occurrence. People should consider in their activity the input of nutrient Si first, and then the variation of water temperature, advocating sustainable development manner. 展开更多
关键词 nutrient water temperature PHYTOPLANKTON temporal-spatial variation harmful algae bloom (HAB) Jiaozhou Bay
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Characteristics of the microzooplankton community in Jiaozhou Bay,Qingdao,China 被引量:6
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作者 陈应华 杨宇峰 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2009年第3期435-442,共8页
The species composition and abundance of microzooplankton at 10 marine and five coastal stations (Hongdao, Daguhe, Haibohe, Huangdao and Hangxiao) in the Jiaozhou Bay (Qingdao, China) were studied in 2001. The mic... The species composition and abundance of microzooplankton at 10 marine and five coastal stations (Hongdao, Daguhe, Haibohe, Huangdao and Hangxiao) in the Jiaozhou Bay (Qingdao, China) were studied in 2001. The microzooplankton community was found to be dominated by Tintinnopsis beroidea, Tintinnopsis urnula, Tintinnopsis brevicoUis and Codonellopsis sp. The average abundance of microzooplankton was highly variable among stations. Specifically, the abundance of microzooplankton was higher at inshore stations and lower in the center of the bay (St. 5), bay mouth (St. 9) and outside the bay (St. 10). The highest average annual densities (346 ind./L) was observed at St. 3, while the lowest (55 ind./L) was at St. 10. Two abundance peaks were recorded in May (324 ind./L) and February (300 ind./L). The distribution of microzooplankton in three sampling layers at the 10 stations was relatively homogenous and the abundance decreased slightly as the water depth increased. At coastal stations, the highest average annual density was recorded at Hongdao Station (677 ind./L), followed by Daguhe Station (616 ind./L), Haibohe Station (400 ind./L ), Huangdao Station (275 ind./L) and Hangxiao Station (73 ind./L). Furthermore, a 24-h sampling analysis conducted at Hangxiao Station revealed that the microzooplankton assemblages were characterized by a bimodal diel vertical migration pattem, with the highest densities occurring at dusk (154 ind./L), followed by dawn (146 ind./L), noon (93 ind./L) and midnight (77 ind./L). The density of microzooplankton in the Jiaozhou Bay was in the middle range of the densities of temperate coastal waters worldwide. 展开更多
关键词 Jiaozhou Bay MICROZOOPLANKTON species composition abundance distribution
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Influence of Seawater Temperature on Phytoplankton Growth in Jiaozhou Bay, China 被引量:6
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作者 杨东方 高振会 +2 位作者 陈豫 王培刚 孙培艳 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2004年第2期166-175,共10页
The phytoplankton reproduction capacity (PRC), as a new concept regarding chlorophyll-a and primary production (PP) is described. PRC is different from PP, carbon assimilation number (CAN) or photosynthetic rate (P B)... The phytoplankton reproduction capacity (PRC), as a new concept regarding chlorophyll-a and primary production (PP) is described. PRC is different from PP, carbon assimilation number (CAN) or photosynthetic rate (P B). PRC quantifies phytoplankton growth with a special consideration of the effect of seawater temperature. Observation data in Jiaozhou Bay, Qingdao, China, collected from May 1991 to February 1994 were used to analyze the horizontal distribution and seasonal variation of the PRC in Jiaozhou Bay in order to determine the characteristics, dynamic cycles and trends of phytoplankton growth in Jiaozhou Bay; and to develop a corresponding dynamic model of seawater temperature vs. PRC. Simulation curves showed that seawater temperature has a dual function of limiting and enhancing PRC. PRC’s periodicity and fluctuation are similar to those of the seawater temperature. Nutrient silicon in Jiaozhou Bay satisfies phytoplankton growth from June 7 to November 3. When nutrients N, P and Si satisfy the phytoplankton growth and solar irradiation is sufficient, the PRC would reflect the influence of seawater temperature on phytoplankton growth. Moreover, the result quantitatively explains the scenario of one-peak or two-peak phytoplankton reproduction in Jiaozhou Bay, and also quantitatively elucidates the internal mechanism of the one- or two-peak phytoplankton reproduction in the global marine areas. 展开更多
关键词 phytoplankton reproduction seawater temperature phytoplankton reproduction capacity Jiaozhou Bay
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Pelagic Nitrogen Cycling in Jiaozhou Bay, a Model Study I: the Conceptual Model 被引量:2
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作者 任玲 张曼平 +2 位作者 Brockmann Uwe H. 冯士笮 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2003年第4期358-367,共10页
A zero dimensional box model (PNCMjzb) with six state variables (ammonium, nitrate, dissolved organic nitrogen, phytoplankton, zooplankton and detritus) was developed to study nitrogen cycling in the Jiaozhou Bay pela... A zero dimensional box model (PNCMjzb) with six state variables (ammonium, nitrate, dissolved organic nitrogen, phytoplankton, zooplankton and detritus) was developed to study nitrogen cycling in the Jiaozhou Bay pelagic ecosystem. The dominant processes within these compartments are considered with nitrogen as flow currency. Phytoplankton and zooplankton are treated as separate state variables, assuming that the species composition was dominated by two or three species the dynamic constants of which are similar and that they represent the entire plankton community. The microbial loop has not been integrated explicitly in the model. The turnover of bacteria is included implicitly in processes such as detritus decomposition, DON remineralization, pelagic nitrification and denitrification. The model is driven by two forcing variables, viz. water temperature and light intensity. Historical data from the1980s and 1990s were compiled and used for model calibration. In this paper (part I), the consideration of every main compartment in the model is interpreted in detail. And the applied equations and parameters are presented. The main results from the simulations together with discussion about phytoplankton dynamics and primary production in Jiaozhou Bay are presented in the next paper (part II). 展开更多
关键词 NITROGEN ecosystem modelling PHYTOPLANKTON NITRATE AMMONIUM PELAGIC Jiaozhou Bay
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EXAMINATION OF SILICATE LIMITATION OF PRIMARY PRODUCTION IN JIAOZHOU BAY, CHINA I. SILICATE BEING A LIMITING FACTOR OF PHYTOPLANKTON PRIMARY PRODUCTION 被引量:31
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作者 杨东方 张经 +2 位作者 吕吉斌 高振会 陈豫 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2002年第3期208-225,共18页
Jiaozhou Bay data collected from May 1991 to February 1994, in 12 seasonal investigations, and provided the authors by the Ecological Station of Jiaozhou Bay, were analyzed to determine the spatiotemporal variations i... Jiaozhou Bay data collected from May 1991 to February 1994, in 12 seasonal investigations, and provided the authors by the Ecological Station of Jiaozhou Bay, were analyzed to determine the spatiotemporal variations in temperature, light, nutrients (NO - 3 N, NO - 2 N, NH + 4 N, SiO 2- 3 Si, PO 3- 4 P), phytoplankton, and primary production in Jiaozhou Bay. The results indicated that only silicate correlated well in time and space with, and had important effects on, the characteristics, dynamic cycles and trends of, primary production in Jiaozhou Bay. The authors developed a corresponding dynamic model of primary production and silicate and water temperature. Eq.(1) of the model shows that the primary production variation is controlled by the nutrient Si and affected by water temperature; that the main factor controlling the primary production is Si; that water temperature affects the composition of the structure of phytoplankton assemblage; that the different populations of the phytoplankton assemblage occupy different ecological niches for C , the apparent ratio of conversion of silicate in seawater into phytoplankton biomas and D , the coefficient of water temperature’s effect on phytoplankton biomass. The authors researched the silicon source of Jiaozhou Bay, the biogeochemical sediment process of the silicon, the phytoplankton predominant species and the phytoplankton structure. The authors considered silicate a limiting factor of primary production in Jiaozhou Bay, whose decreasing concentration of silicate from terrestrial source is supposedly due to dilution by current and uptake by phytoplankton; quantified the silicate assimilated by phytoplankton, the intrinsic ratio of conversion of silicon into phytoplankton biomass, the proportion of silicate uptaken by phytoplankton and diluted by current; and found that the primary production of the phytoplankton is determined by the quantity of the silicate assimilated by them. The phenomenon of apparently high plant nutrient concentrations but low phytoplankton biomass in some waters is reasonably explained in this paper. 展开更多
关键词 PHYTOPLANKTON silicon limiting factor Jiaozhou Bay
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Zooplankton community structure,abundance and biovolume in Jiaozhou Bay and the adjacent coastal Yellow Sea during summers of 2005–2012:relationships with increasing water temperature 被引量:1
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作者 WANG Weicheng SUN Song +2 位作者 ZHANG Fang SUN Xiaoxia ZHANG Guangtao 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2018年第5期1655-1670,共16页
Zooplankton abundance, biovolume and taxonomic composition in Jiaozhou Bay and the adjacent coastal Yellow Sea were evaluated using ZooScan measurement of samples collected by net towing every August from 2005 to 2012... Zooplankton abundance, biovolume and taxonomic composition in Jiaozhou Bay and the adjacent coastal Yellow Sea were evaluated using ZooScan measurement of samples collected by net towing every August from 2005 to 2012. Zooplankton abundance and biovolume ranged from 1 938.5 to 24 800 ind./m^3 and 70.8 to 1 480.1 mm^3/m^3 in Jiaozhou Bay and 73.1 to 16 814.3 ind./m^3 and 19.6 to 640.7 mm^3/m^3 in the coastal Yellow Sea. Copepods were the most abundant group in both regions, followed by N octiluca scintillans and appendicularians in Jiaohzou Bay, and chaetognaths and N octiluca scintillans in adjacent coastal Yellow Sea. Over the study period, the most conspicuous hydrographic change was an increase in water temperature. Meanwhile, a general decrease in zooplankton abundance was observed, particularly in copepod populations. Based on redundancy analysis(RDA), the warming trend was the key environmental factor influencing to decrease of copepod abundance. The proportion of small-sized copepods increased while the mean size of all copepods decreased, in significant correlation with water temperature. Our results indicate that zooplankton, particularly copepods, are highly sensitive to change in water temperature, which is consistent with predicted impacts of warming on aquatic ectotherms. Due to their dominance in the zooplankton, the decline in copepod size and abundance could lead to an unfavourable decrease in energy availability for predators, particularly planktivorous fish. 展开更多
关键词 copepod ABUNDANCE body size ZooScan temperature northwestern Yellow Sea
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Silicon limitation on primary production and its destiny in Jiaozhou Bay,China Ⅶ:The complementary mechanism of the earth ecosystem 被引量:8
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作者 杨东方 高振会 +2 位作者 杨应斌 孙培艳 王鑫平 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2006年第4期401-412,共12页
In this paper, the phenomenon that the variation in nutrient and water temperature could cause changes in phytoplankton growth and structure is examined; and the question of how a marine ecosystem make up the earth ec... In this paper, the phenomenon that the variation in nutrient and water temperature could cause changes in phytoplankton growth and structure is examined; and the question of how a marine ecosystem make up the earth ecosystem step by step to auto-sustain the balance between phytoplankton and nutrient supply especially Si is discussed. Three major complementary mechanisms of the earth ecosys- tem for nutrient Si, water temperature and carbon were put forward. Understanding the mechanisms nowadays would explain the why the El Nifio and La Nifia occurred, and forecast the trend of human-impacted the earth, which would alert us with proactive countermeasures. 展开更多
关键词 nutrient Si PHYTOPLANKTON marine ecosystem earth ecosystem complementary mechanism
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Examination of Silicate Limitation of Primary Production in Jiaozhou Bay,North ChinaⅢ.Judgment Method,Rules and Uniqueness of Nutrient Limitation Among N,P,and Si 被引量:28
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作者 杨东方 高振会 +2 位作者 陈豫 张经 王培刚 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2003年第2期114-133,共20页
Analysis and comparison of Jiaozhou Bay data collected from May 1991 to February 1994(12 seasonal investigations) provided by the Ecological Station of Jiaozhou Bay revealed the characteristic spatiotemporal variation... Analysis and comparison of Jiaozhou Bay data collected from May 1991 to February 1994(12 seasonal investigations) provided by the Ecological Station of Jiaozhou Bay revealed the characteristic spatiotemporal variation of the ambient concentration Si:DIN and Si:16P ratios and the seasonal variation of Jiaozhou Bay Si:DIN and Si:16P ratios showing that the Si:DIN ratios were < 1 throughout the year in Jiaozhou Bay; and that the Si:16P ratios were < 1 throughout Jiaozhou Bay in spring, autumn and winter. The results proved that silicate limited phytoplankton growth in spring, autumn and winter in Jiaozhou Bay. Analysis of the Si:DIN and Si:P ratios showed that the nutrient Si has been limiting the growth of phytoplankton throughout the year in some Jiaozhou Bay waters; and that the silicate deficiency changed the phytoplankton assemblage structure. Analysis of discontinuous 1962 to 1998 nutrient data showed that there was no N or P limitation of phytoplankton growth in that period. The authors consider that the annual cyclic change of silicate limits phytoplankton growth in spring, autumn and winter every year in Jiaozhou Bay; and that in many Jiaozhou Bay waters where the phytoplankton as the predominant species need a great amount of silicate, analysis of the nutrients N or P limitation of phytoplankton growth relying only on the N and P nutrients and DIN:P ratio could yield inaccurate conclusions. The results obtained by applying the rules of absolute and relative limitation fully support this view. The authors consider that the main function of nutrient silicon is to regulate and control the mechanism of the phytoplankton growth process in the ecological system in estuaries, bays and the sea. The authors consider that according to the evolution theory of Darwin, continuous environmental pressure gradually changes the phytoplankton assemblage's structure and the physiology of diatoms. Diatoms requiring a great deal of silicon either constantly decrease or reduce their requirement for silicon. This will cause a series of huge changes in the ecosystem so that the whole ecosystem requires continuous renewal, change and balancing. Human beings have to reduce marine pollution and enhance the capacity of continental sources to transport silicon to sustain the continuity and stability in the marine ecosystem.nt 展开更多
关键词 PHYTOPLANKTON SILICATE limiting factor Jiaozhou Bay
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Silicon limitation on primary production and its destiny in Jiaozhou Bay, China Ⅷ: The variation of atmospheric carbon caused by both phytoplankton and human 被引量:1
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作者 杨东方 苗振清 +2 位作者 石强 陈豫 陈国光 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第2期416-425,共10页
Statistical analysis on data collected in the Jiaozhou Bay (Shandong, China) from May 1991 to February 1994 and those collected in Hawaii from March 1958 to December 2007 shows dynamic and cyclic changes in atmospheri... Statistical analysis on data collected in the Jiaozhou Bay (Shandong, China) from May 1991 to February 1994 and those collected in Hawaii from March 1958 to December 2007 shows dynamic and cyclic changes in atmospheric carbon in the Northern Pacific Ocean (NPO), as well as the variation in space-time distribution of phytoplankton primary production and atmospheric carbon in the study regions. The study indicates that the human beings have imposed an important impact on the changing trends of the atmospheric carbon. Primary production in the Jiaozhou Bay presents a good example in this regard. In this paper, dynamic models of the atmospheric carbon in the NPO, the cyclic variations in the atmospheric carbon, and primary production in the Jiaozhou Bay are studied with simulation curves presented. A set of equations were established that able to calculate the rate and acceleration of increasing carbon discharged anthropologically into the atmosphere and the conversion rate of phytoplankton to atmospheric carbon. Our calculation shows that the amount of atmospheric carbon absorbed by one unit of primary production in the Jiaozhou Bay is (3.21–9.74)×10-9/(mgC·m-2d-1), and the amount of primary production consumed by a unit of atmospheric carbon is 102.66–311.52 (mgC·m-2d-1/10-6). Therefore, we consider that the variation of atmospheric carbon is a dynamic process controlled by the increase of carbon compound and its cyclic variation, and those from anthropologic discharge, and phytoplankton growth. 展开更多
关键词 atmospheric carbon carbon conversion human beings PHYTOPLANKTON Jiaozhou Bay Hawaii
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Seasonal variation in fatty acid composition of seston and the copepod Calanus sinicus(Brodsky,1962)in Jiaozhou Bay and its trophic implications 被引量:5
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作者 刘梦坛 李超伦 孙松 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2011年第6期1164-1173,共10页
The fatty acid compositions of seston and Calanus sinicus were investigated to study trophic relationships in Jiaozhou Bay. Principal component analysis was carried out to ordinate the fatty acid patterns of seston in... The fatty acid compositions of seston and Calanus sinicus were investigated to study trophic relationships in Jiaozhou Bay. Principal component analysis was carried out to ordinate the fatty acid patterns of seston in stations and months. The results showed that diatoms were most abundant in the phytoplankton at station A5 (located in the northwest of the bay: 36~9'N, 120~20'E) and least abundant at station D7 (located outside of the bay: 35~59'N, 120~26'E). By contrast, dinoflagellates were most abundant at station D7 and least abundant at station A5. According to the annual variations of 16:1 (o7 and 18:4(o3/ 16:1(o7, diatoms flourished mainly in spring and summer, while dinoflagellates bloomed exclusively in summer. A distinctive feature of the fatty acid composition of C. sinicus was the prevalence of 20:5o3 and 22:6(o3. The higher content of 16:1(o7 over 18:4(o3 in females indicated that diatoms contributed more than dinoflagellates to the diet of C. sinicus. The feeding intensity of C. sinicus on diatoms was higher in spring and autumn than in other seasons. The herbivorous indicators 20:1 and 22:1 were comparatively low, suggesting that besides phytoplankton, C. sinicus might feed on a wider range of particles including organic detritus, bacteria and small copepods. 展开更多
关键词 fatty acid SESTON Calanus sinicus trophic relationships
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Examination of Silicate Limitation of Primary Production in Jiaozhou Bay, China Ⅱ. Critical Value and Time of Silicate Limitation and Satisfaction of the Phytoplankton Growth 被引量:32
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作者 杨东方 张经 +2 位作者 高振会 陈豫 孙培艳 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2003年第1期46-63,共18页
Analysis and comparison of Jiaozhou Bay data collected from May 1991 to February 1994 revealed the spatiotemporal variations of the ambient Si(OH) 4∶NO 3 (Si∶N) concentration ratios and the seasonal variations of (S... Analysis and comparison of Jiaozhou Bay data collected from May 1991 to February 1994 revealed the spatiotemporal variations of the ambient Si(OH) 4∶NO 3 (Si∶N) concentration ratios and the seasonal variations of (Si∶N) ratios in Jiaozhou Bay and showed that the Si∶N ratios were < 1 throughout Jiaozhou Bay in spring, autumn, and winter. These results provide further evidence that silicate limits the growth of phytoplankton (i.e. diatoms) in spring, autumn and winter. Moreover, comparison of the spatiotemporal variations of the Si∶N ratio and primary production in Jiaozhou Bay suggested their close relationship. The spatiotemporal pattern of dissolved silicate matched well that of primary production in Jiaozhou Bay. Along with the environmental change of Jiaozhou Bay in the last thirty years, the N and P concentrations tended to rise, whereas Si concentration showed cyclic seasonal variations. With the variation of nutrient Si limiting the primary production in mind, the authors found that the range of values of primary production is divided into three parts: the basic value of Si limited primary production, the extent of Si limited primary production and the critical value of Si limited primary production, which can be calculated for Jiaozhou Bay by Equations (1), (2) and (3), showing that the time of the critical value of Si limitation of phytoplankton growth in Jiaozhou Bay is around November 3 to November 13 in autumn; and that the time of the critical value of Si satisfaction of phytoplankton growth in Jiaozhou Bay is around May 22 to June 7 in spring. Moreover, the calculated critical value of Si satisfactory for phytoplankton growth is 2.15-0.76 μmol/L and the critical value of Si limitation of phytoplankton growth is 1.42-0.36 μmol/L; so that the time period of Si limitation of phytoplankton growth is around November 13 to May 22 in the next year; the time period of Si satisfactory for phytoplankton growth is around June 7 to November 3. This result also explains why critical values of nutrient silicon affect phytoplankton growth in spring and autumn are different in different waters of Jiaozhou Bay and also indicates how the silicate concentration affects the phytoplankton assemblage structure. The dilution of silicate concentration by seawater exchange affects the growth of phytoplankton so that the primary production of phytoplankton declines outside Jiaozhou Bay earlier than inside Jiaozhou Bay by one and half months. This study showed that Jiaozhou Bay phytoplankton badly need silicon and respond very sensitively and rapidly to the variation of silicon. 展开更多
关键词 PHYTOPLANKTON limitation and satisfaction critical value Jiaozhou Bay
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