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71.
An estrogen receptor (ER)/androgen receptor (AR) ligand competitive binding assay (ER/AR-binding assay) and chemical analyses were used to evaluate the endocrine disrupting chemicals (EDCs) behavior of two municipal wastewater treatment plants (WWTPs) (K and S). In the influents, estrone (E1), androsterone (A), androstenedione (AD), BPA (bisphenol A), NP (nonylphenol) and daidzein (DZ) were detected in high amounts with subsequent 24 h-average concentrations of 350, 1000, 29, 1300, 3900, and 5700 ng/L in K-WWTP and of 310, 620, 59, 1600, 2600, and 8400 ng/L in S-WWTP. The estrogenic (androgenic) activity as 17 -estradiol (E2) equivalents (EEQ) or testosterone (Te) equivalents (TEQ) was consequently 620 ng E2/L (570 ng Te/L) and 580 ng E2/L (800 ng Te/L) for the two WWTPs. The removal e ciencies of the above mentioned sole target chemicals were 51%–100% for K-WWTP and 55.6%–100% for S-WWTP. The removal e ciencies of EEQ were about 73% for both WWTPs, while the removal e ciencies of TEQ were 62.1% for K-WWTP and 98.4% for S-WWTP. In addition, chemical-derived EEQ were about 1.2%–52.4% of those by ER-binding assay for K-WWTP and the corresponding ratios were 1.3%–83.3% for S-WWTP, while chemical derived TEQ were less than 3% of values measured by the AR-binding assay for both WWTPs.  相似文献   
72.
Many butterflies acquire nutrients from non-nectar sources such as puddles. To better understand how male Papilio butterflies identify suitable sites for puddling, we used behavioral and electrophysiological methods to examine the responses of Japanese Papilio butterflies to Na+, K+, Ca2+, and Mg2+. Based on behavioral analyses, these butterflies preferred a 10-mM Na+ solution to K+, Ca2+, and Mg2+ solutions of the same concentration and among a tested range of 1?mM to 1?M NaCl. We also measured the ion concentrations of solutions sampled from puddling sites in the field. Na+ concentrations of the samples were up to 6?mM, slightly lower than that preferred by butterflies in the behavioral experiments. Butterflies that sipped the 10?mM Na+ solution from the experimental trays did not continue to puddle on the ground. Additionally, butterflies puddled at sites where the concentrations of K+, Ca2+, and/or Mg2+ were higher than that of Na+. This suggests that K+, Ca2+, and Mg2+ do not interfere with the detection of Na+ by the Papilio butterfly. Using an electrophysiological method, tip recordings, receptor neurons in contact chemosensilla inside the proboscis evoked regularly firing impulses to 1, 10, and 100?mM NaCl solutions but not to CaCl2 or MgCl2. The dose?Cresponse patterns to the NaCl solutions were different among the neurons, which were classified into three types. These results showed that Japanese Papilio butterflies puddle using Na+ detected by the contact chemosensilla in the proboscis, which measure its concentration.  相似文献   
73.
液氨泄漏可引起火灾、爆炸和中毒事故,针对液氨泄漏中毒事故的危害,提出了采用有毒作业分级方法和液氨泄漏扩散半径估算法评估液氨使用场所的潜在危险程度和危害范围,给出了评估实例。  相似文献   
74.
通过田间小区试验及大田示范的对比,研究了专用叶面营养液的适宜喷期及其对水稻的生理特性:根系活力、养分吸收、叶片叶绿素含量、光合速率等和产量的影响.研究结果表明:适宜喷期在植后7-10天,并喷施1次,效果最好.专用叶面营养液使水稻根系活力在分蘖盛期、灌浆期明显提高;显著提高分蘖盛期叶片及灌浆期剑叶的叶绿素含量,促进剑叶提高光合速率及水稻对N、P、K营养的吸收;增加水稻灌浆期剑叶蛋白质含量.水稻喷施叶面营养液在生理上发生显著变化,促进分蘖增加,有效穗增加,稻秆矮壮,通过增加水稻灌浆期叶片的光合能力而加速碳水化合物向穗部的输送,达到增加千粒重及产量的目的.  相似文献   
75.
This paper reports on the photodecomposition of aqueous humic acid (HA) by a TiO2-coated ceramic foam filter (TCF) reactor and on the potential for the formation of disinfection byproducts (DBPs) upon chlorination of the photocatalytically treated solutions. This photocatalytic reactor can also be applied to the removal of natural organic matter (NOM) in swamp waters. The proposed photocatalytic reaction system was operated as per standardized methodologies. First, the ability of the TCF to decompose HA (a representative compound of NOM) was evaluated from the changes in the total organic carbon (TOC) and UV254 with the reaction time. Remarkably, TOC removal and UV254 values ranging from 44% to 61% and from 60% to 83%, respectively, were achieved. The potential for the formation of DBPs (total trihalomethane and total haloacetic acid) by chlorination of the phototreated solution was strongly dependent on the TOC removal and UV254 values in the solution. The degree of photodecomposition of NOMs in the swamp water samples and the DBP formation potential showed similar trends as in the case of the standard solutions containing HA. The method used in this study could be effectively used to evaluate the efficiency of TCF for reducing HA and NOM, while suppressing the formation of DBP products.  相似文献   
76.
OBJECTIVE: To quantify the dynamic loads and intervertebral motions throughout the cervical spine during simulated rear impacts. METHODS: Using a biofidelic whole cervical spine model with muscle force replication and surrogate head and bench-top mini-sled, impacts were simulated at 3.5, 5, 6.5, and 8 g horizontal accelerations of the T1 vertebra. Inverse dynamics was used to calculate the dynamic cervical spine loads at the centers of mass of the head and vertebrae (C1-T1). The average peak loads and intervertebral motions were statistically compared (P < 0.05) throughout the cervical spine. RESULTS: Load and motion peaks generally increased with increasing impact acceleration. The average extension moment peaks at the lower cervical spine, reaching 40.7 Nm at C7-T1, significantly exceeded the moment peaks at the upper and middle cervical spine. The highest average axial tension peak of 276.9 N was observed at the head, significantly greater than at C4 through T1. The average axial compression peaks, reaching 223.2 N at C5, were significantly greater at C4 through T1, as compared to head-C1. The highest average posterior shear force peak of 269.5 N was observed at T1. CONCLUSION: During whiplash, the cervical spine is subjected to not only bending moments, but also axial and shear forces. These combined loads caused both intervertebral rotations and translations.  相似文献   
77.
Journal of Material Cycles and Waste Management - The influence of temperature and storage time on hydrogen sulphide (H2S) emissions from two different dairy manures was investigated over four...  相似文献   
78.
Hydrothermal treatment of model food garbage focusing on the effects of additional foreign matter has been performed in subcritical conditions as a pretreatment for the next step, i.e., the bio-processing and production of liquid feed or fertilizer. Using the hydrothermal technique, we studied the temporal change in internal temperature and pressure in a reactor on the elapsed heating time to check the equipment safety in terms of temperature and pressure. The gaseous and water-soluble liquid was also characterized to investigate the feasibility of retrieving valuable chemicals and emitting environmentally hazardous substances. From the changes in the internal temperature and pressure curve, the maximum temperature and pressure were 196 °C and 1.42 MPa for 30-min elapsed heating time, which was below the predefined temperature limits of 200 °C and pressure of 1.55 MPa. No such irregular behavior was observed in the temperature and pressure curve except that it was a little different for the foreign matter detergent, which also was within the limits. The qualitative and quantitative analysis of end products showed that the emitted malodorous substances and chemicals were further below the threshold levels for Japan.  相似文献   
79.
在边坡地震响应数值模拟中,科学合理地选取边坡计算模型的边界范围是决定模拟结果准确性的关键因素之一。基于有限元数值模拟方法,分别建立了边坡前缘和后缘两组边界尺寸不同的概化模型,选取了两条不同特性的实际地震动记录作为输入,计算了各边坡模型的动力响应,探索了边坡前缘和后缘尺寸的影响规律,验证了远置边界在边坡地震稳定性分析中的可用性。结果表明:(1)在边坡地震响应数值模拟中,边坡模型的前缘尺寸应至少设定为坡高的 2 倍、后缘尺寸应至少设定为坡高的 4 倍,才能避免边界的地震波反射叠加效应,以便得到更为准确的模拟结果;(2)设置黏弹性边界和远置边界工况下得到的边坡地震安全系数相差 0.02,说明合理的远置边界可以运用到边坡地震稳定性分析当中。  相似文献   
80.
Journal of Polymers and the Environment - In this investigation, the use of phosphotungstic acid (PWA) and phosphomolybdic acid (PMA) as well as Zn2+ containing kaolin and bentonite explored for...  相似文献   
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