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591.
基于中国278个地级市2006~2020年面板数据,运用渐进双重差分模型(DID)评估国家自主创新示范区政策实施对地区碳排放量与质的影响及作用机制,并对处理效应的异质性问题展开讨论.研究发现:国家自主创新示范区有效驱动了碳排放的量降质升(平均值为-0.078和0.108);国家自主创新示范区能通过提升能源利用效率、驱动绿色技术创新以及推进产业结构合理化,最终实现有效降碳;国家自主创新示范区在不同经济发展阶段的地区发挥了不同的政策效用,在东部与经济增速较慢地区对碳排放的抑制作用更有成效,对中西部与经济增速较快地区碳生产率的提升效果更为明显. 相似文献
592.
593.
有机氮(ON)在雨水径流氮素污染中起关键作用,但多数研究只关注可生物降解有机氮的生物转化去除,忽略了占比较高的难生物降解有机氮.以生物炭作为吸附剂,探究其对雨水径流典型难生物降解有机氮(吲哚)的吸附效能及机制.结果表明,原始生物炭对吲哚有较高的单位吸附量(45 mg·g-1),生物炭投加浓度为0.4 g·L-1时其表面平均吸附位点利用度最高.H2O2和NaOH改性生物炭对吲哚的吸附量是原始生物炭的1.3倍和1.6倍,吸附机制包括疏水相互作用、氢键和π-π电子供体-受体(π-π EDA)作用,以疏水相互作用为主,其中H2O2改性通过增加生物炭表面含氧官能团来加强氢键和π-π EDA作用,而NaOH改性生物炭通过大幅提高生物炭比表面积来加强疏水相互作用,故NaOH改性吸附效果更优.综上,生物炭对难生物降解有机氮具有较强去除作用,通过NaOH改性还能大幅提高效率,故在雨水径流氮素污染较高的地区把NaOH改性生物炭作为生物滞留池中的填料有着极大的应用潜力. 相似文献
594.
INTRODUCTION: The purpose of this investigation was to identify beliefs, driving personality dispositions, and behaviors that distinguish self-defined aggressive drivers from non-aggressive drivers. METHOD: Telephone surveys were used to identify self-reported aggressive drivers (n=305) who were compared to non-aggressive drivers (n=1,715) concerning their beliefs, driving behaviors, and self-described driving dispositions. RESULTS: Aggressive drivers, compared to non-aggressive drivers, were less concerned about speeding, aggressive driving, and cell phone use while driving, yet were more likely to have had an encounter with another aggressive driver. They were also more likely to report that they had driven when they knew they had too much to drink, yet they felt less likely that they would be stopped by the police. CONCLUSION: Aggressive drivers display many dispositions that define them as high risk drivers and public information/motivational campaigns alone will likely be ineffective with this group of drivers. Strategies that combine visible enforcement with widespread publicity campaigns appear to be necessary. 相似文献
595.
OBJECTIVE: Previous methods to determine spinal ligament deformation have included either custom-designed transducers or computational methods using rigid body transformation of kinematic data. Goals of the present study were to describe a computational methodology to determine dynamic deformations of an arbitrarily oriented ligament in a spine specimen and its associated errors. METHODS: Calculation of ligament deformation in a spinal segment with vertebral motion tracking flags utilized digital stereophotography, lateral neutral posture radiograph, and detailed quantitative anatomy to develop geometrical relationships between flag markers and ligament attachment points. A custom jig, consisting of two flags each with four markers, was constructed to quantify errors associated with computed ligament deformation, flag marker translation, and flag rotation. RESULTS: Average error in ligament deformation was dependent upon motion direction and ranged between 0.03 mm (SD 0.45 mm) and 0.28 mm (SD 0.18 mm). Average error for flag marker translation ranged between 0.02 mm (SD 0.14 mm) and 0.11 mm (SD 0.39 mm), and for flag rotation ranged between -0.06 degrees (SD 0.17 degrees ) and 0.07 degrees (SD 0.12 degrees ). CONCLUSIONS: Accuracy of the present technique was equivalent to or greater than that of previous methods. The present technique utilized relatively cost-effective digital stereophotography, and may be used to calculate strain in ligaments not readily accessible for transducer application. The methodology has wide-spread applicability for analyses of dynamic or static spinal or other ligament strains, and may be used to determine spinal canal and intervertebral foramen narrowing and area reduction. 相似文献
596.
OBJECTIVE: Intervertebral Neck Injury Criterion (IV-NIC) hypothesizes that dynamic three-dimensional intervertebral motion beyond physiological limit may cause multiplanar soft-tissue injury. Present goals, using biofidelic whole human cervical spine model with muscle force replication and surrogate head in head-turned rear impacts, were to: (1) correlate IV-NIC with multiplanar injury, (2) determine IV-NIC injury threshold at each intervertebral level, and (3) determine time and mode of dynamic intervertebral motion that caused injury. METHODS: Impacts were simulated at 3.5, 5, 6.5, and 8 g horizontal accelerations of T1 vertebra (n = 6; average age: 80.2 years; four male, two female donors). IV-NIC was defined at each intervertebral level and in each motion plane as dynamic intervertebral rotation divided by physiological limit. Three-plane pre- and post-impact flexibility testing measured soft-tissue injury; that is significant increase in neutral zone (NZ) or range of motion (RoM) at any intervertebral level, above baseline. IV-NIC injury threshold was average IV-NIC peak at injury onset. RESULTS: IV-NIC extension peaks correlated best with multiplanar injuries (P < 0.001): extension RoM (R = 0.55) and NZ (R = 0.42), total axial rotation RoM (R = 0.42) and NZ (R = 0.41), and total lateral bending NZ (R = 0.39). IV-NIC injury thresholds ranged between 1.1 at C0-C1 and C3-C4 to 2.9 at C7-T1. IV-NIC injury threshold times were attained between 83.4 and 150.1 ms following impact. CONCLUSIONS: Correlation between IV-NIC and multiplanar injuries demonstrated that three-plane intervertebral instability was primarily caused by dynamic extension beyond the physiological limit during head-turned rear impacts. 相似文献
597.
The use of ozone in the remediation of polycyclic aromatic hydrocarbon contaminated soil 总被引:3,自引:0,他引:3
The potential of using ozone for the removal of phenanthrene from several different soils, both alone and in combination with biodegradation using a microbial inoculant (Pseudomonas alcaligenes PA-10), was examined. The greater the water content of the soil the less effective the ozone treatment, with air-dried soils showing the greatest removal of phenanthrene; while soils with higher levels of clay also reduced the effectiveness of the ozone treatments. However, at least a 50% reduction in phenanthrene levels was achieved in air-dried soil after an ozone treatment of 6 h at 20 ppm, with up to 85% removal of phenanthrene achieved in sandy soils. The biodegradation results indicate that P. alcaligenes PA-10 may be useful as an inoculant for the removal of PAHs from contaminated soils. Under the conditions used in our experiments, however, pre-ozonation did not enhance subsequent biodegradation of phenanthrene in the soils. Similar levels of phenanthrene removal occurred in both non-ozonated and ozonated Cruden Bay soil inoculated with P. alcaligenes PA-10. However, the biodegradation of phenanthrene in ozonated Boyndie soil was much slower. This may be due to the release of toxic products in this soil during ozonation. 相似文献
598.
Antić MP Jovancićević BS Ilić M Vrvić MM Schwarzbauer J 《Environmental science and pollution research international》2006,13(5):320-327
Background, Aims and Scope It is well known that the composition of petroleum or some of its processing products changes in the environment mostly under
the influence of microorganisms. A series of experiments was conducted in order to define the optimum conditions for an efficient
biodegradation of petroleum pollutant, or bioremediation of different segments of the environment. The aim of these investigations
was to show to what extent the hydrocarbons of a petroleum pollutant are degraded by microbial cultures which were isolated
as dominant microorganisms from a surface water of a wastewater canal of an oil refinery and a nitrogen plant. Biodegradation
experiments were conducted on one paraffinic, and one naphthenic type of petroleum during a three month period under aerobic
conditions, varying the following parameters: Inorganic (Kp) or an organic medium (Bh) with or without exposition to light.
Methods Microorganisms were analyzed in a surface water sample from a canal (Pančevo, Serbia), into which wastewater from an oil
refinery and a nitrogen plant is released. The consortia of microorganisms were isolated from the water sample (most abundant
species: Phormidium foveolarum - filamentous Cyanobacteria, blue-green algae and Achanthes minutissima, diatoms, algae). The
simulation experiments of biodegradation were conducted with the biomass suspension and crude oils Sirakovo (Sir, paraffinic
type) and Velebit (Ve, naphthenic type). After a three month period, organic substance was extracted by means of chloroform.
In the extracts, the content of saturated hydrocarbons, aromatic hydrocarbons, alcohols and fatty acids was determined (the
group composition). n-Alkanes and isoprenoid aliphatic alkanes, pristane and phytane, in the aliphatic fractions, were analyzed
using gas chromatography (GC). Total isoprenoid aliphatic alkanes and polycyclic alkanes of sterane and triterpane types were
analyzed by GC-MS.
Results and discussion. Paraffinic type petroleums have a significant loss of saturated hydrocarbons. For naphthenic type petroleum,
such a trend has not been observed. The most intensive degradation of n-alkanes and isoprenoid aliphatic alkanes (in paraffinic
oil) and isoprenoids (in naphthenic oil) was observed using the inorganic medium Kp in the light; the microbial conversion
is somewhat lower with Kp in the dark; with organic medium Bh in the light the degradation is of low intensity; with the same
medium in the dark the degradation is hardly to be seen. Steranes and triterpanes were not affected by microbial degradation
under the conditions used in our experiments. Obviously, the petroleum biodegradation was restricted to the acyclic aliphatics
(n-alkanes and isoprenoids).
Conclusion Phormidium foveolarum (filamentous Cyanobacteria - blue-green algae) and Achanthes minutissima (diatoms, algae), microbial
cultures isolated as dominant algae from a surface water in a wastewater canal of an oil refinery and a nitrogen plant, have
degradable effects dominantly involving petroleum hydocarbons. Petroleum microbiological degradation is more intensive when
inorganic medium (in the light) is applied. Having in mind that the inorganic pollutants have been released into the canal
as well, this medium reflects more the natural environmental conditions. Polycyclic alkanes of sterane and triterpane type,
in spite of the fact that these compounds could be degraded, have remained unchanged regarding abundance and distribution.
Since this is the case even for naphthenic type petroleum (which is depleted in n-alkanes), it can be concluded that the biodegradation
of petroleum type pollutants, under natural conditions, will be restrained to the n-alkane and isoprenoid degradation.
Recommendation and Outlook Performed experiments and simulations of petroleum microbiological degradation may serve for the prediction of the fate of
petroleum type pollutants, as well as for definition of conditions for bioremediation of some environmental segments. 相似文献
599.
The discrepancy between verbal and actual commitment in waste recycling and environmental behavior is thought to have attenuated
the effectiveness of many environmental policy and measures. Studies purport to show the existence of such a value-action
gap in environmental issues has been largely based on matching the verbal commitment to environmental value through self-reported
environmental behavioral data. Therefore, there is a lack of direct evidence to prove that such a discrepancy exists. This
study demonstrates a methodology (contrasting on-site observation with self-reported results) to measure the gap between verbal
commitment and actual recycling behavior and provides an explanation on the recycling behavior of students at Hong Kong Baptist
University in the hope that the lessons learnt can be generalized to a wider context. Our findings indicate that a gap between
verbal recycling commitment and corresponding action does exist in waste recycling on this university campus. By using multiple
linear regression analysis, we found that the self-reported recycling behavior of undergraduates cannot be meaningfully explained
by most variables previously suggested in the general value-action model. 相似文献
600.
一次亵渎法律的不公正判决比十次犯罪危害更大。因为后者污染的是水流 ,而前者污染的是水源。1997年5月11日 ,国务院召开全国安全生产电视电话会议。时任国务院副总理的朱基传达了江泽民总书记对安全生产工作的重要指示 :要坚决树立安全生产第一的思想 ,坚决贯彻执行安全生产的规章制度 ,坚决改变那种纪律松弛、管理不严、有章不循的情况 ,确保安全生产。国务院副总理吴邦国在电视电话会议上强调 ,现在距香港回归只剩下50多天 ,党的十五大也将召开 ,一定要做好安全生产工作 ,创造一个良好的环境。1997年5月12日至18日 ,… 相似文献