三种鳗鲡肌肉无机元素组成分析

采用电感耦合等离子体发射光谱仪对花鳗鲡、欧洲鳗鲡和日本鳗鲡肌肉无机元素组成进行测定。结果证明 :花鳗鲡肌肉中 Ca含量最高 ,P含量次之 ;而欧洲鳗鲡和日本鳗鲡肌肉中 P含量最高 ,Ca含量次之 ;三种鳗鲡肌肉中 Na、Mg、K含量相近。花鳗鲡肌肉中常量元素和某些微量元素 ( Zn、Fe、Mn)的含量高于欧洲鳗鲡和日本鳗鲡。可认为花鳗鲡在无机元素营养方面优于另二种鳗鲡。在花鳗鲡人工配合饲料中 ,无机元素用量应高于另二种鳗鲡 ,尤其是 Ca、P、Zn和 Fe

Plane strain asymptotic fields for cracks terminating at the interface between elastic and pressure-sensitive dilatant materials

The plane strain asymptotic fields for cracks terminating at the interface between elastic and pressure-sensitive dilatant material are investigated in this paper. Applying the stress-strain relation for the pressure-sensitive dilatant material, we have obtained an exact asymptotic solution for the plane strain tip fields for two types of cracks, one of which lies in the pressure-sensitive dilatant material and the other in the elastic material and their tips touch both the bimaterial interface. In cases, numerical results show that the singularity and the angular variations of the fields obtained depend on the material hardening exponent n, the pressure sensitivity parameter mu and geometrical parameter lambda

Biodiversity of the ectomycorrhiza on the rare and endangered tree species Tuga chinensis tchekiangensis(Flous) Cheng in Wuyishan Nature Reserve

对武夷山国家级自然保护区残遗与濒危树种南方铁杉植物群落历经了6年的调查,共采集了123种外生菌根,经显微与超显微技术鉴定了84种,这一结果是迄今为止已发表的,在同一树种中菌根类型最多的记录.它不仅证明了武夷山地区的菌物区系由于处于东西相连,南北贯通的位置上,而且从区系成分上据有温热两带俱全的特点,因而形成生物多样性,并从共生菌的角度再度揭示了物种协同进化的规律.Systematic investigation was made on ectomycorrhizae in the woods of a variety of Tsuga chinensis,tchekiangensis(Flous) Cheng,in Wuyishan Nature Reserve in the past six years.During that period,120 ectomycorrhiza samples were collected and 84 types identified by analysing their macro-micro-and ultrastructure.This is the first time that so many types of mycorrhiza in the forests of the species are reported on.This result has proved Wuyishan's geographical position at the cross where a fungi growing area links the east and west,south and north.Thus the region owns the characteristics of both the temperate and the subtropical zone and it is thus such peculiarity whereby its biodiversity is created.Moreover,considering the results of this investigation in the regard of symbiosis between plants and fungi,their co-evolution is ascertained once more.国家自然科学基金资助项目(39770004);; 福建省自然科学基金资助项目(C97003,D0410002

2018—2019年中国宏观经济预测

\"中国季度宏观经济模型(CQMM)\"课题组于2018年2月发布了中国季度宏观经济模型(CQMM)第二十四次预测。预测显示,今明两年,全球经济的持续增长将继续拉动中国的对外贸易增长,同时,消费增长仍将维持稳定,但国内投资增长的减速也会继续抑制经济增长。物价方面,CPI会较2017年明显提升,突破2%的水平,但仍处于较温和的价格上涨状态,PPI则呈现高位增长回落的态势,二者的负向缺口将出现萎缩。总体上,今明两年中国经济有望保持6.50%以上的水平,经济增长\"稳中趋缓\"的态势还将延续。模拟研究发现,在当前经济投资构成下,\"降杠杆\"与\"稳增长\"之间,可能存在两难困境,应通过加快民间投资增速,以补偿\"降杠杆\"可能造成的经济增速下降,实现\"降杠杆\"与\"稳增长\"的双重目标。政策当局应抓住今明两年国内外经济的有利时机,综合应用各项政策措施,在防控金融风险的同时,将政策重点放在激发民营经济活力,促进民间投资增速的快速回升之上。国家社科基金重大项目“需求结构转换背景下提高消费对经济增长贡献研究”(15ZDC011);;教育部哲学社会科学重大课题攻关项目“地方债发行机制与监管研究”(14JZD011);教育部哲学社会科学重大课题攻关项目“中国经济潜在增速的测算与展望研究”(15JZD016);教育部哲学社会科学重大课题攻关项目“供给侧结构改革的理论基础与政策思路研究”(16JZD016);;教育部重点研究基地重大项目“中国季度宏观经济模型(CQMM)的再拓展”(17JJD790014);;中央高校基本科研业务费“中国实践背景的现代宏观经济理论与政策”(20720151037

Study on the variation of the iodine nutrition status among children aged 8 to 10 and pregnant women in Xiamen city after the implement of new standard of iodized salt supply

目的研究新标碘盐供应前后厦门市沿海8-10岁儿童和孕妇的碘营养变化情况,为下一步碘缺乏病防控策略调整提供实证依据。方法在新标碘盐供应前及食用新标碘盐后的第3、6、9个月调查厦门市翔安区8-10岁学生和孕妇的尿碘、尿比重、碘盐覆盖率、碘盐合格率、合格碘盐食用率和居民日人均食盐摄入量。结果自来水水碘含量为4.2μg/l,基线调查、第二、三次评估日人均食盐摄入量均数分别为5.7、6.9、6.9 g;基线调查、第一、第二、三次评估,8-10岁学生碘盐合格率和合格碘盐食用率都分别为97.1、93.1、98.0和98.0,盐碘中位数分别为28.7、24.7、24.0、25.3 Mg/kg,尿碘中位数分别为132.0、177.7、181.7和134.5μg/l,尿比重均值分别为1.0157、1.0196、1.0213和1.0184;孕妇碘盐合格率分别为97.8%、84.6%、84.4%和90.2%,盐碘中位数分别为27.8、25.7、24.3和23.7Mg/kg,尿碘中位数分别为103.8、128.5、138.9和100.2μg/l,尿比重均值分别为1.0123、1.0153、1.0180和1.0143;尿碘与采样季节、气候及尿比重有关,尿碘值与尿比重呈正相关关系。结论新标碘盐实施前后,8-10岁儿童碘营养总体处于适宜水平,但孕妇碘营养均不足,要采取措施加强孕妇碘营养,保障人群健康素质。Objective To investigate the variation of iodine nutrition among children aged 8 to 10 and pregnant women after the implement of new standard of iodized salt supply, and to provide evidence for the further adjustment of control strategy against iodine deficiency disease.Method Survey has been performed to acquire the urinary iodine, specific gravity, iodized salt coverage rate, iodized salt qualification rate, qualified iodized salt consumption rate and average daily salt intake among children aged 8 to10 and pregnant women in Xiamen city.It has been conducted for 3 times repeatedly with a regular interval of 3 months after the implement of new standard.Results The tap water iodine content was 4.2 μg / L.The average daily salt intake of baseline survey, second and third assessment was 5.7, 6.9 and 6.9 g respectively.The iodized salt coverage rates among children aged 8 to10 and pregnant women were all reached 100% in 4 assessments.Among children aged 8 to 10, iodized salt qualification rate and qualified iodized salt consumption rate for 4 assessments were 97.1, 93.1, 98.0 and 98.0 respectively.Median of iodine salt samples was 28.7, 24.7, 24.0 and 25.3 mg / kg, respectively.The median of urinary iodine was 132.0,1 77.7, 181.7 and134.5 μg / L,respectively.The mean of specific gravity was 1.0184, 1.0157, 1.0196 and 1.0213, respectively.Among the pregnant women, the iodized salt qualification rate and qualified iodized salt consumption rate of pregnant women were 97.8, 84.6, 84.4 and 90.2%, respectively.Median of iodine salt samples was 27.8, 25.7, 24.3 and 23.7 mg / kg, respectively.Median of urinary iodine was 103.8, 128.5, 138.9 and 100.2 μg / L,respectively.Mean of specific gravity was 1.0123,1.0153,1.0180 and 1.0143, respectively.Urinary iodine was correlated with season of sampling, climate and specific gravity, and urinary iodine was positively correlated with specific gravity.Conclusion The iodine nutrition status of children aged 8 to 10 was remained in adequate level regardless of the implement of new standard of iodized salt.However, the results suggested that the corresponding indicator among pregnant women was in a relatively low level.Proper countermeasure should be taken to enhance the iodine su-pply among them and to further secure the quality of general population

Use of an ADCP to Compute Suspended Sediment Concentration in the Qiongzhou Strait

根据琼州海峡西口一测站4个季节的声学多普勒流速剖面仪(简称AdCP)回波强度数据以及现场采集的水样反演了悬沙浓度(SSC).结果显示,春季悬沙浓度为0.017--0.05 kg/M3,平均0.025 kg/M3,夏季悬沙浓度为0.012--0.026 kg/M3,平均0.017 kg/M3,秋季悬沙浓度为0.012--0.074 kg/M3,平均0.028 kg/M3,冬季悬沙浓度为0.012--0.1kg/M3,平均0.028 kg/M3,悬沙的沉积和再悬浮跟潮流密切相关,各季节流速的不同导致夏季悬沙浓度明显的小于其他季节,大小潮流速的差别导致大潮期间的悬沙浓度大于小潮期间的悬沙浓度.观测点海水和悬沙由表到底都是全年向西输送,春季净输沙量为-7.5x104kg,夏季净输沙量为-1.3x104kg,秋季净输沙量为-3.03x105kg,冬季净输沙量为-1.05x105kg.The data were gathered during a water monitoring campaign which deployed ADCP and in situ bottle samplers in west of Qiongzhou Strait.Calibrated the backscattered ADCP signals against in-situ bottle samples of the suspended sediment,suspended sediment concentration(SSC) can be computed.The suspended sediment concentration computed in the Qiongzhou Strait with the equation show that the current magnitude effect the concentration of sediments in suspension.The average SSC in spring,summer,autumn and winter is 0.025,0.017,0.028,0.028 kg/m3,respectively.Average current velocity in the four season is 39.6,26.8,50.2,45.8 cm/s,respectively,The high concentrations of suspended material coincide with the higher current magnitudes,which induce increased bed shear stresses and vertical mixing.Conversely,suspended sediment concentration levels are markedly reduced.The net sediment transport in spring,summer,autumn and winter is-7.5×104,-1.3×104,-3.03×105,-1.05×105 kg,respectively,negative value means the net sediment move from east to west.The net sediment transport from east to west all the year long in the study site.国家“908”专项(908-01-ST09)资

The Relationship Between Theoretical Depth Datum and Tidal Diffusion Analysis in Jiulongjiang Estuary

根据2006年3月九龙江河口区6个潮位观测站的周月资料,参考2000年2月的潮汐数据,对比分析河口区潮汐特征的经年变化,并探讨了潮波衰减模数μ与底摩阻作用的关系.分析表明九龙江河口区的潮汐性质属正规半日潮,2006年数据推算的理论最低潮面与2000年同期数据推算结果相比普遍偏低,上游河段降低幅度大于下游,沿程理论最低潮面变化幅度趋缓;潮波振幅衰减模数μ值减小了2.5~5.5倍.产生变化的原因是九龙江河口区平面自然状态和水深地形特征的改变,为河床底高降低、底坡趋于平缓、底质的变化;这些变化可能与上游河段采沙、造航、围垦等人类的开发活动有关.Based on more than one month long observations at six tidal gauges in the Jiulongjiang Estuary in February 2000 and in March 2006,respectively,tidal changes in spring were compared and analyzed,and then the relationship between tidal attenuation coefficient μ and the bottom friction were discussed.Analysis indicates that tidal type in Jiulongjiang Estuary is characterized by informal semi-diurnal tides.Compared with the theoretical depth datum in 2000,the theoretical depth datum in 2006 depressed,and the decrease in the upriver reach was more than that in the downriver reach.By comparison,it was also found that the tidal attenuation coefficient μ in 2006 was reduced by 60%~80% relative to that in 2000,which can be ascribed to the landform changes in the Jiulongjiang Estuary,including the riverbed lowering,the base slope smoothing,and the changes in sediment component.These changes may be related to human activities in the upstream such as sand excavation,reclamation,and so on

大量相干光源驱动和种子激光系统

The photoinjector and seed laser systems of DCL

A new method for low-temperature direct wafer bonding of InP/GaAs

通过对 InP/GaAs 异质键合实验方法的研究,提出了包括表面活化处理、真空预键合和退火热处理的三步法,在350℃低温下实现了InP/GaAs异质材料的键合。界面电流 电压(I V)特性的研究表明,350℃样品的界面过渡层极薄,电子主要以隧穿方式通过界面,而450℃的扩散使得过渡层增厚,界面电流 电压特性可视为双肖特基二极管的反向串联。同时,对键合样品也进行了拉力测试,实验结果表明 450℃样品的键合强度优于350℃样品。最后,对InP/GaAs异质材料的键合机理进行了探讨。Based on the research of the direct wafer bonding of InP/GaAs, we proposed a novel method, which includes surface preparation, prebonding in vacuum and an elevated temperature anneal, and bonded InP/GaAs successfully at low-temperature (350℃). Through the study of current versus voltage (I-V) character, we found the interlayer between GaAs and InP was so thin that the carrier can tunnel across the heterobarrier bonded at 350℃. But the interlayer became thick when the annealing temperature reached 450℃, and the I-V character can be seen as the reverse tandem of two schottky diode. Bonded interfaces were also characterized by tensile-strength measurement and revealed that the bonding strength at 450℃ was stronger than that of 350℃. Finally, we discussed the mechanism of InP/GaAs meterials.国家自然科学基金资助项目(60006004