高危岗位矿工心理倦怠对注意执行功能的影响

为探究心智游移在倦怠和注意执行功能间的作用机制,有效减少由负性心理状态引起的不安全行为,降低人因事故发生率。在文献研究的基础上,引入心智游移,采用SART范式和AX-CPT范式,以问卷筛选出的100位国有煤炭企业高危岗位作业人员为研究对象,讨论倦怠、心智游移和个体注意执行功能之间的关系。研究结果表明:高频AX试次会引起惯性反应偏向,被试者需要更多的时间来维持线索字母A和解决无效线索B与有效探针X之间的冲突;高倦怠矿工比低倦怠矿工的注意执行控制功能更易受到高频心智游移的影响;心智游移在倦怠与注意执行功能间起到调节作用。     

芒苞草（芒苞草科）种子的无菌萌发研究

选取野外采回的芒苞草种子为材料,研究无菌水和不同状态Ms培养基以及不同激素种类和浓度对芒苞草种子萌发的影响,并初步探讨了芒苞草幼苗的生长情况.结果表明:经4℃的低温春化处理2 mo后,播种在无菌水中的芒苞草种子萌发率可达95%,比同样条件下MS液体(25.1%)和固体(10.4%)培养基中的萌发率高;在有关激素影响的实验中,无菌水中6-BA和GA,对种子萌发没有促进作用,液体MS培养基中的1.0 mg/L GA,明显促进种子萌发,而固体MS培养基中0.5 mg/L 6-BA对种子萌发的促进作用较明显,1.0 mg/L 6.BA有利于从生芽的诱导.将无菌水和液体MS培养基中已发芽的芒苞草种子转移至固体MS培养基中培养可长成小植株.     

转Bt基因玉米种植对土壤细菌数量及多样性的影响

利用三室根箱装置获得玉米生长室土壤(S I)、根际土(SⅡ)、非根际土(SⅢ)3个不同根区土壤,采用传统平板计数培养与变性梯度凝胶电泳(DGGE)技术相结合的方法,研究了转基因玉米Btll及其非转基因亲本在播种后40、50、60 d各根区土壤细菌数量及多样性的变化.结果表明,转Bt基因玉米播种后50、60 d S I根区土壤可培养细菌数量显著低于非转基因亲本,播种后40、50 d SⅡ根区土壤可培养细菌数量较亲本玉米显著增加,而在其他时期和根区与亲本玉米之间均无显著差异.DGGE图谱显示,3个采样时期各根区DGGE图谱条带数、土壤细菌多样性指数和均匀度指数均无显著差异(P＞0.05).     

黑龙江、松花江和嫩江冰坝凌汛发生原因及预报方法

利用1951-2000年水文、气象资料,在对黑龙江、松花江、嫩江发生的特大冰坝的年份监测中分析发现,冰坝发生大多在二江同时发生,个别年份有三江同时发生,并有群发特点。冰坝发生前,秋季降水多,河槽蓄水量多,河流水位高;冬季降雪多、气温低;春季开江期,有明显的降水和升温过程,是冰坝的形成和凌汛发生的重要原因。并且分析冰坝发生前期高空环流形势特点,依此研制了冰坝凌汛预报方法。     

Fragmented seagrass habitats on the Mediterranean coast, and distribution and abundance of mysid assemblages

Four different habitats were sampled in order to determine the spatial and temporal distribution and abundance of mysids in a seagrass meadow ecosystem. These habitats included meadows of Posidonia oceanica and Cymodocea nodosa, the edge of P. oceanica meadow and sandy substrates. Three random sites for each habitat were sampled along the coast of Alicante at different times, using a hand-net technique (6 m²). Seven species of mysids were identified: Leptomysis posidoniae, Leptomysis buergii, Paramysis helleri, Siriella clausii, Mesopodopsis slabberi, Siriella armata and Mysidopsis gibbosa. Total abundance of mysids was highest at the edge of the P. oceanica meadow, followed by the C. nodosa meadow, sandy substrate and P. oceanica meadow, respectively (P<0.05); this pattern was found during all sampling periods except one. Three species showed persistent spatial segregation by habitat (S. clausii in Posidonia; L. posidoniae at the edge; S. armata in Cymodocea), whereas the other four did not show any clear segregation by habitat (ANOVA, P<0.01). On a site scale (km), spatial variability was very high. Multivariate analyses confirm the existence of differences in the assemblage structure among habitats, with a gradual change from the Posidonia meadow to sand. Posidonia and Cymodocea showed different mysid assemblages. Fragmented, shallow, vegetated habitat on the Mediterranean coast seems to support a higher abundance and species richness of mysids, through habitat diversification, in comparison with homogeneous habitats.     

己烯雌酚与四溴双酚A对小球藻生长效应的影响（Effects of Diethylstilbestrol and Tetrabromobisphenol A on Growth of Chlorella pyrenoidosa）

采用化学品对藻类毒性测试的标准试验方法,分别研究了己烯雌酚和四溴双酚A单组分对小球藻生长及光合色素含量的影响,并用相加指数法评价了己烯雌酚和四溴双酚A双组分对小球藻的联合毒性效应.结果表明,藻细胞密度和光合色素含量随己烯雌酚和四溴双酚A浓度增加而明显下降,且均表现出较好的浓度-效应关系,其对小球藻的96h-EC50值分别为0.0248mg·L-1和0.0455mg·L-1;两者对小球藻96h的联合毒性效应为拮抗作用.     

Substrate catabolism related to reproduction in the bay scallop Argopecten irradians concentricus,as determined by O/N and RQ physiological indexes

Weight specific rates of oxygen consumption carbon dioxide production, and ammonia-N excretion, measured for a Florida population of the bay scallop Argopecten irradians concentricus between May and September, 1982 and October and November, 1983 were significantly correlated (P<0.0005) to environmental factors that co-varied seasonally with metabolic shifts related to reproduction. Mean O/N and CO₂/O₂ (RQ) molar ratios indicates that scallop energy metabolism varied over the course of the reproductive cycle. Resting stage individuals (May-early June) had RQ values close to 0.7, indicative of a predominantly lipid-based metabolism. During the initial stages of gametogenesis (late June-early July) scallops catabolized primarily carbohydrate, as evidenced by maximum O/N (>22) values and RQ values close to 1.0 RQ values >1.0 indicated a possible carbohydrate to lipid conversion during the period of cytoplasmic growth (late July-early September). As gametes matured and spawning commenced (late September-November), metabolism became primarily protein based, as indicated by O/N and RQ values around 9.0 and 0.8, respectively. This pattern of substrate catabolism supports existing data on the storage and utilization of specific energy reserves with respect to reproduction in this species.     

Transport and fate of organic wastes in groundwater at the Stringfellow hazardous waste disposal site, southern California

In January 1999, wastewater influent and effluent from the pretreatment plant at the Stringfellow hazardous waste disposal site were sampled along with groundwater at six locations along the groundwater contaminant plume. The objectives of this sampling and study were to identify at the compound class level the unidentified 40-60% of wastewater organic contaminants, and to determine what organic compound classes were being removed by the wastewater pretreatment plant, and what organic compound classes persisted during subsurface waste migration. The unidentified organic wastes are primarily chlorinated aromatic sulfonic acids derived from wastes from DDT manufacture. Trace amounts of EDTA and NTA organic complexing agents were discovered along with carboxylate metabolites of the common alkylphenolpolyethoxylate plasticizers and nonionic surfactants. The wastewater pretreatment plant removed most of the aromatic chlorinated sulfonic acids that have hydrophobic neutral properties, but the p-chlorobenzene-sulfonic acid which is the primary waste constituent passed through the pretreatment plant and was discharged in the treated wastewaters transported to an industrial sewer. During migration in groundwater, p-chlorobenzenesulfonic acid is removed by natural remediation processes. Wastewater organic contaminants have decreased 3- to 45-fold in the groundwater from 1985 to 1999 as a result of site remediation and natural remediation processes. The chlorinated aromatic sulfonic acids with hydrophobic neutral properties persist and have migrated into groundwater that underlies the adjacent residential community.     

是负责任的行动还是公关?非政府组织对志愿举措的看法

非政府组织倾向于高度怀疑工业界对志愿举措的促进,特别是当它们似乎被用来证明去掉法规有理或妨碍独立监测与评估时更加如此.此外,非政府组织还把矛头指向由于缺乏信息或缺乏多利害攸关者参与而产生的严重可信度差距.减少可信度差距和提高志愿举措的有效性的行动,要包括创造更大的透明度、允许独立验证、包含性、可持续性价值的内化、和互补性使用一种使之有能力的法规框架.     

飞行器隔热瓦1200℃性能测试中接触热阻影响仿真与验证

目的 建立统一的飞行器隔热材料性能测试标准。方法 利用数值方法对飞行器隔热瓦1 200℃热环境性能测试中的传热模型进行计算。设计3种不同热导率和表面粗糙度的绝热材料隔热性能对比试验。在考虑接触面间凹凸点完全接触导热、接触间隙介质导热和相邻界面辐射传热联合作用时,能够获得与实测数据基本一致的计算结果。结果 试验证明,接触热阻是导致实测数据与理想传热结果相悖的主要原因。获得了接触热阻条件下热扩散系数随传热过程的变化关系,定量得到了相同测试条件下给定的3种不同热导率与粗糙度底部绝热材料对隔热性能测试结果的影响。结论 测试结果存在较大偏差的主要原因是表面粗糙度所致,两接触面在高温条件下更有利于热流传播。研究结果可为飞行器热防护系统设计与性能考核试验方案的确定提供重要参考依据。