One-step preparation of polyimide-inlaid amine-rich porous organic block copolymer for efficient removal of chlorophenols from aqueous solution

A novel polyimide-inlaid amine-rich porous organic block copolymer (PI-b-ARPOP) was prepared via one-step polymerization by using different molar ratios of melamine (MA)/terephthalaldehyde (TA)/pyromellitic dianhydride (PMDA), at molar ratios of 4/3/1, 4/2/2 and 4/1/3. The copolymer contained both aminal groups belonging to ARPOP and imide groups belonging to PI, and the bonding styles of the monomers and growth orientations of the polymeric chains were diversiform, forming an excellent porous structure. Notably, MA/TA/PMDA (4/2/2) had a surface area and pore volume of 487.27?m²/g and 1.169?cm³/g, respectively. The adsorption performance of the materials towards 2,4-dichlorophenol (2,4-DCP) in ultra-pure water was systematically studied. The pH value of 7 was optimal in aqueous solution. Na⁺ and Cl^? ions did not negatively affect the adsorption process, while humic acid (HA) slightly decreased the capacity. The equilibrium time was 40 sec, and the maximum adsorption capacity reached 282.49?mg/g at 298?K. The removal process was endothermic and spontaneous, and the copolymer could maintain its porous structure and consistent performance after regeneration by treatment with alkali. Moreover, to further assess the practical applicability of the material, the adsorption performance towards 2,4-DCP in river water was also investigated. This paper demonstrated that the PI-b-ARPOP can be an efficient and practical adsorbent to remove chlorophenols from aqueous solution.     

校正系数在工作曲线中应用

采用大肚移液管，将标准溶液配制成整数级别的贮备液、中间液、使用液时，利用工作曲线计算测定值需要引入校正系数，利用该方法可简化操作，减少误差提高实验准确度、精密度。     

卤代核苷植物油悬液一次注射法体内姐妹染色单体交换形成试验

本文介绍一种体内姐妹染色单体交换形成试验的新方法。将卤代核苷制成植物油悬液作皮下一次注射,当小鼠体内卤代核苷剂量达到500mg/kg时,即可获得非常满意的骨髓细胞姐妹染色单体分化着色效果。该法操作简便,无需特殊设备,卤代核苷用量亦较小。     

南海市废水重点污染源的特征与筛选方法

根据调查所得的南海市废水污染源，按照规范的评价标准和筛选原则，同时结合行业因素确定选标准，筛选出重点污染源１５６家，占全市调查工业企业数的３．４％，等标污染负荷量占调查负荷总量的８７．６％，重点污染源主要分布在陶瓷，铝型材，纺织印染，电镀，造纸和制革等６个行业，流域分布主要在西江及佛山水道。     

连云港海州湾海域赤潮生物的种类调查及形成原因

以光学显微镜对在2003-2006 年连云港海州湾附近海域采集的浮游生物进行观察,初步鉴定出赤潮的种类,并对形成赤潮的原因进行了分析,期望该调查分析结果对于海州湾附近海域生态研究,摸清赤潮的成因和过程,定期监测,减少灾害的发生有一定的促进作用.     

高羊茅对微生物强化修复石油污染土壤影响的研究

进行了石油污染土壤在外源微生物菌剂和高羊茅协调作用下的强化修复试验,对外源微生物菌剂在不同植被条件下的去除特征进行了分析.分别进行了没有植物、高羊茅草坪、高羊茅草种新育草坪3种不同情况下的降解试验.结果表明,微生物菌剂对石油污染土壤有着良好的降解效果,去除率为36%～43%,而没有微生物菌剂和植被作用下的对照组的去除率仅为5.74%～6.0%;高羊茅草坪能够提高微生物进一步降解的能力,在直接铺草坪的情况下,去除率可以达到51%～62%;在播种高羊茅草种,形成新嫩草坪的情况下,去除率为48%～54%.结果表明,在直接铺高羊茅草坪条件下,微生物菌剂的强化分解作用可以提高41.6%～44.2%,在新嫩草坪作用下能够提高27.9%～30.6%,可以认为高羊茅草坪对于提高微生物菌剂的强化分解有一定的促进作用.在试验过程中还对不同修复的土壤pH值变化特性进行了分析.     

Effects of a non-ionic surfactant (Tween-80) on the mineralization, metabolism and uptake of phenanthrene in wheat-solution-lava microcosm

Effects of a non-ionic surfactant (Tween-80) on the mineralization, metabolism and uptake of phenanthrene in wheat-solution-lava microcosm were studied using 14C-labeled phenanthrene. The mineralization and metabolism of phenanthrene were fast in such a system. At least 90% of the applied phenanthrene were transformed within 24 days. Only 0.3% of the applied 14C-activity were identified to be the parent phenanthrene. Most of the applied 14C-activity (70%) was recovered from wheat, in which ca. 70% were associated with wheat shoots (stems and leaves) and ca. 30% wheat roots. 33% and 20% of the applied 14C-activity had been constructed into wheat tissues of shoots and roots, respectively. The 14C-activity recovered in forms of CO2 and volatile organic chemicals (VOCs) was 12-16% and 4-5%, respectively. The major metabolites of phenanthrene were polar compounds (18% of the applied 14C) and only 2.1% were identified as non-polar metabolites. No phenanthrene was found in wheat shoots indicating that it could not be transported from roots to upper parts of the plant but in form of metabolites (mostly polar metabolites). Foliar uptake of 14C-activity via air in form of 14CO2 occurred. The presence of Tween-80 significantly enhanced the degradation of phenanthrene, which could be attributed to its increase of microbial activities in the system. Tween-80 also significantly (P < 0.05) reduced the phenanthrene level in wheat roots, which probably resulted from desorption of phenanthrene from root surface caused by the surfactant.     

A／A／O微曝氧化沟处理城市污水的工程设计

以某日处理量为80000m^3城市污水处理厂为例，介绍了A／A／O微曝氧化沟工艺的设计思路及参数选择，能够满足设计要求，且可信度高，有实用参考价值。     

Intensity and daily pattern of passenger vehicle use by region and class in China: estimation and implications for energy use and electrification

Given the explosive growth of the passenger vehicle market and energy demands in China, research on vehicle-use intensity and driver-travel patterns is critical for better assessing travel demand and its implications for alternative fuel vehicles, energy security, and environmental policies. This study attempts to estimate annual vehicle kilometers traveled (AVKT) per privately-owned passenger vehicle and their daily distance patterns by vehicle class and geographic region. The data sample from a survey consists of 169,292 privately owned passenger vehicles, made by 177 car manufacturers during 2003–2018, running in 82 cities from 27 provincial regions. The log-transformed average AVKT is estimated to be 12,377 km with 95% probability ranging from 5490 to 28,579 km. The investigation reveals that vehicles from South China have the highest AVKT at 13,320 km. Generally, vehicles in small cities have higher AVKT than in big cities, except AVKT of tier 1 cities being higher. Another trend is that more expensive or larger vehicles tend to be driven more. A model is fitted for estimating AVKT based on region, city type, automaker, price range, and certain vehicle features including class and age. Data of daily commuting distances in recent years are also analyzed. The average daily commuting distances typically range from 21 to 28 km. Using the validated Gamma distribution method, daily distance distributions are specified for different regions. It is found that 99% of the daily driving distance is no more than 88.0–112.0 km, depending on region. Utility factors of plug-in electric vehicles are also estimated to be much higher than those based on driving data in the USA. These findings suggest global mitigations strategies on vehicle fuel use, electrification, and greenhouse gases should consider vehicle-use intensity at the regional level.

     

Factors influencing purchase of electric vehicles in China

Mitigation and Adaptation Strategies for Global Change - The development of electric vehicle (EV) market has significant implications on reducing oil consumption and greenhouse gas emissions. It...