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Rain-source urban rivers are an important part of the urban ecosystem. Due to the small water environment capacity and the rapid development of the regional economy and society, they are vulnerable to serious pollution. The goal of this study was to identify the main pollution characteristics of river water quality and to carry out a scientific comprehensive water quality assessment. Water samples from 12 sampling locations of the Longgang River in Shenzhen, a typical rain-source urban river, were collected from January to December in 2018. According to the Environmental Quality Standard for Surface Water (GB 3838-2002), 22 water quality indicators were analyzed, and the water quality of Longgang River was comprehensively evaluated using the single-factor assessment method, comprehensive pollution index method, and principal component analysis method. The results of the single-factor assessment method showed that water quality of all sampling sites of the Longgang River met the Class V of the Environmental Quality Standard for Surface Water (GB 3838-2002), and the Tiaojiao Shui and Longxi River met the Class Ⅳ and Class Ⅲ of the Environmental Quality Standard for Surface Water (GB 3838-2002), respectively. The results of the comprehensive pollution index method showed that the water quality of 12 sampling sites was clean or relatively clean. Both the results of the comprehensive pollution index and principal component comprehensive score showed that the water quality of Longxi River, Nanyue River, and Tianjiao Shui were the best among all sampling sites. There is still room for improvement in the Wutongshan River, Dakang River, Ailian River, Dingshan River, and Huangsha River, and significant consideration should be given to parameters such as nutrients (TN, TP, and NH

Obstructive sleep apnea-hypopnea syndrome (OSAHS) is widely known for its multiple systems damage, especially neurocognitive deficits in children. Since their discovery, adenosine A

This paper proposes a limited discrete operation points control strategy for series hybrid electric tracked-vehicle. First, to optimize the control parameters of rule-based energy management strategy, particle swarm optimization algorithm is employed. the optimization results were applied to determine the optimal switch strategy between operation points of the engine. Second, a dynamic adaptive strategy is also proposed to achieve the coordinated control of the engine-generator set. Finally, with combination of above parts, a detailed energy management strategy and coordinated control system was proposed. The results demonstrate that the discrete operation points control strategy combined with coordinated control strategy can improve the electricity power supply performance, decrease the fluctuations of the system and stabilize the bus voltage and guarantee robust control performance.

Obstructive sleep apnea-hypopnea syndrome (OSAHS) is widely known for its multiple systems damage, especially neurocognitive deficits in children. Since their discovery, adenosine A2A receptors (A2ARs) have been considered as key elements in signaling pathways mediating neurodegenerative diseases such as Huntington's and Alzheimer's, as well as cognitive function regulation. Herein, we investigated A2AR role in cognitive impairment induced by chronic intermittent hypoxia (CIH). Mice were exposed to CIH 7 h every day for 4 weeks, and intraperitoneally injected with A2AR agonist CGS21680 or A2AR antagonist SCH58261 half an hour before IH exposure daily. The 8-arm radial arm maze was utilized to assess spatial memory after CIH exposures.To validate findings using pharmacology, the impact of intermittent hypoxia was investigated in A2AR knockout mice. CIH-induced memory dysfunction was manifested by increased error rates in the radial arm maze test. The behavioral changes were associated with hippocampal pathology, neuronal apoptosis, and synaptic plasticity impairment. The stimulation of adenosine A2AR exacerbated memory impairment with more serious neuropathological damage, attenuated long-term potentiation (LTP), syntaxin down-regulation, and increased BDNF protein. Moreover, apoptosis-promoting protein cleaved caspase-3 was upregulated while anti-apoptotic protein Bcl-2 was downregulated. Consistent with these findings, A2AR inhibition with SCH58261 and A2AR deletion exhibited the opposite result. Overall, these findings suggest that A2AR plays a critical role in CIH-induced impairment of learning and memory by accelerating hippocampal neuronal apoptosis and reducing synaptic plasticity. Blockade of adenosine A2A receptor alleviates cognitive dysfunction after chronic exposure to intermittent hypoxia in mice.

Veterinary antibiotics can enter into croplands with animal excrement and can have effects on nitrification and denitrification processes in the agricultural soils. A field experiment was conducted to evaluate the effect of sulfamethazine (SMZ) on N

The reactive nitrogen (Nr) pollution is a serious environmental problem. A wise application of nitrogen fertilizer is important for mitigating Nr loss. Field experiments were undertaken during the direct-seeded rice and winter-wheat growing seasons from 2014 to 2015 in Nanjing, one of the typical rice-wheat rotation regions in China, to evaluate the potential of different nitrogen fertilizers for mitigating Nr (N2O, NH3 emissions, and NO3− leaching) losses. Seven different fertilizer treatments were included in this study: a no fertilizer treatment (NF), conventional fertilizer (CF), urea-ammonium mixed nitrogen fertilizer (UA), stabilized urea (UHD; urea + hydroquinone + dicyandiamide), sulfur-coated urea (SCU), urea formaldehyde (UF) and organic fertilizer (OF). In comparison with the CF, all the fertilizer treatments except for UA decreased NH3 volatilization by 14.5–36.0% (p

Red phosphors CaMoO4:Eu3+ were synthesized by microwave method with MnO2 as microwave absorbent. The phase structure and luminescent properties of the as-synthesized phosphors were investigated by X-ray powder diffraction and Fluorescence spectrophotometer. The results show that when the reaction time was 40 min, microwave power was medium-high fire (~560 W), we got the tetragonal CaMoO4:Eu3+ pure phase. The excitation spectrum of CaMoO4:Eu3+ was composed by a broad band between 200 nm and 350 nm and a series of peaks from 350 nm to 500 nm. The main peak was at 305 nm. The emission spectrum was composed of a series of peaks in the range of 550~750 nm and the main peak was at 617 nm due to the 5D0→7F2 transition of Eu3+. Doping charge compensator Li+, Na+ or K+ could improve the luminous intensity of the sample. When the doping amount of Li+, Na+ or K+ were 8 mol%, the luminous intensity of the sample reached the maximum. The intensity of the emission peak at 617 nm was 4.04, 3.42, 3.48 times of sample without doping charge compensator.

A new enzyme-catalyzed asymmetric construction of chiral tertiary alcohols via asymmetric aldol reactions between β,γ-unsaturated α-keto esters and ketones was reported. Proteinase from Aspergillus melleus (AMP) was used as a sustainable biocatalyst. The best results can be obtained with yields of up to 90%, diastereoselectives of up to 93:7 dr, and enantioselectivities of up to 70% ee. This work not only expands the application of enzymatic promiscuity, but also provides more examples for constructing chiral tertiary alcohols.

Agriculture soil is one of major sources of greenhouse gas (GHG) emissions. A wise use of nitrogen (N) fertilizer is important for mitigating GHG emissions. To evaluate the potential of different fertilizers treatments to mitigate total GHG emissions, a field experiment was conducted to investigate nitrous oxide (N2O), methane (CH4) and ammonia (NH3) emissions and nitrate (NO3−) leaching from a typical rice and winter wheat rotation system in Southeast China. Six reduced N treatments (including single reducing N input, increasing potassium input, combined application of urea ammonium (UA) and organic fertilizer (OF), single application of urea with hydroquinone and dicyandiamide (UHD) and urea formaldehyde (UF)) and the local practice (conventional N fertilizer) were applied in the study. Most of the reduced N treatments tended to reduce the cumulative CH4, N2O and NH3 emissions and NO3− leaching relative to the local practice, while single application of UHD during the rice season obviously increased the CH4 and NH3 emissions (p

Veterinary antibiotics have been widely detected in croplands due to the application of animal excrements as fertilizer. However, their effects on ammonia (NH

The removal of oil from simulated oily wastewater by catalyzed oxidation with immobilized laccase was investigated. The effects of several main factors, such as pH, the amount of laccase, temperature, and reaction time, were discussed in detail. The results indicated that the optimum condition for immobilized laccase-catalyzed removal of oil was as follows: 25 mL simulated oily wastewater with the oil concentration of 120 mg/L in phosphate buffer (0.1 M, pH 4.5), reacted with 0.7696 g immobilized laccase and 100 mg/L chitosan at 25°C for 6 h. The oil removal efficiency was as high as 86% under the optimum conditions. Mg2+ and Cu2+ ions had little effect on the oil removal efficiency of immobilized laccase, but Fe2+ reduced the oil removal efficiency. The effect of the support on oil removal efficiency could be neglected. The immobilized laccase demonstrated a reliable and stable reusability.

The proposed Jinping-I hydropower station is located on the middle reach of the Yalongjiang River, Sichuan Province, P.R. China. It consists of a double-curvature arch dam with a maximum height of 305 m, which will be the highest in the world. Excavation disturbed zone (EDZ) in the left bank slope is one of the most important aspects in slope stability and deformation evaluation. This paper is focused on estimation of EDZ in the left bank slope of Jinping-I hydropower station based on numerical simulation. Geological conditions of the left bank slope are firstly analyzed. Then, displacement field of the slope during excavation is calculated by finite element method (FEM). It can be indicated that the model and parameters in this paper is reasonable by comparing observed results with calculated ones. EDZ in the left bank slope can be estimated based on the calculated displacement field. It can be inferred that the range of EDZ is related to the controlling discontinuities such as fault f42-9 and Lamprophyre X etc. which are adjacent to the excavation line.

Based on the investigation of the Huanghai Sea and the Bohai Sea in Spring( April to May) of 2014, the concentrations of urea and inorganic nitrogen were determined respectively by diacetyl monoxime-Semicarbazide Hydrochloride method and Spectrophotometric method. The distribution of urea and the component of dissolved nitrogen were analyzed. The influencing factors of urea were also discussed. The results showed that the concentration of urea in the Bohai sea and the Huanghai sea ranged from 0.21-2.17 μmol x L(-1), and the average concentration was (0.84 ± 0.20) μmol x L(-1). Urea was an important component of the dissolved organic nitrogen (DON) and accounted for 7.90% of DON. In the investigated area, the average concentration of urea in the north Huanghai sea was the highest, and that in the south Huanghai sea was the lowest. The concentration of urea in the Huanghai sea gradually reduced from inshore to offshore. The areas with high concentrations of urea were near the coastal cities like Qingdao and Dalian where have high population density. The concentration of urea in Bohai sea gradually increased form inshore to offshore, this result indicated that the river input was not the primary source and this might be caused by adsorption of colloid flocculation.

Using two conventional aromatic rice cultivars and one hybrid aromatic rice combination, effects on the quality of aromatic rice were studied by spraying zinc and other multiple nutrient elements under the field experiment.The results showed that by spraying Zn, ZnMg，ZnMgK and ZnMgKFeCu MoCoB on heading stage and followed on the 7th and 14th day after the heading stage, the rate of brown rice, milled rice and head rice, the score of aroma and eating and the content of protein were improved, the chalky rice rate, chalkiness and amylose content were reduced and at the same time the length of rice gel was elongated, therefore the processing quality, appearance quality, cooking and eating quality and nutrient quality of aromatic rice were improved to some extent. The highest quality of aromatic rice was achieved by spraying the combination of Zn and all the other multiple nutrient elements, followed by spraying ZnMgK, ZnMg and Zn solely.

Based on the experiment of two inbred aromatic rice varieties and one hybrid aromatic rice line treated under four different temperatures( daymean temperature 21°C, 23°C, 26°C and 30°C respectively) during grain filling stage in phytotrons, the shape and arrangement of endosperm starch granules in rice grain transection were observed by scanning electron microscope and the related characteristics of rice grain qualities of chalky percent and chalkiness were analyzed at the same time. The results showed that under the lower temperature( daymean temperature21°C and 23°C), many large compound starch granules with clear angulars packed together regularly without significant natural gaps bewteen starch granules in the tansectional endosperm. However, with the increase of temperature, starch granules in the transectional endosperm were changed from regularly shaped and closely and orderly arranged to various shaped and chaoticly arranged with obvious natural gaps between starch granules, which was closely consistent with the poorer appearance quality under the higher temperature, which indicated that the endosperm structure is closely related with appearance quality of aromatic rice.

Changes of the content of starch, amylose and the activities of 3 key enzymes involved in starch synthetic metabolism in developing rice grains under four different temperature in phytotrons during grain filling stage of two aromatic rice varieties were studied. The results showed that compared with that under the lower temperature (21°C and 23°C), the content of starch and amylose and the activities of SBE and GBSS under higher temperatures (26°Cand 30°C) were generally higher at the beginning of the grain filling stage and obviously lower during the middle and late grain filling stage, with the exception of the activity SSS which were always higher under lower temperature. The relationship between the changes of activities of SSS, SBE and the variation of starch accumulating rate was very close and so did the relationship between GBSS activity and the amylose content. The lower activities of SSS, SBE and GBSS during the middle and late grain filling stage may be the key physiological factors which lead to the poorer progress quality and appearance quality of aromatic rice under high temperature.

The ageing of copper foils and Copper foils-surfaced in UV rays are studied by 3D Video, SEM, EDX, which shows that copper foils and Copper foils-surfaced are in different level of ageing; embossment and crack which are the most obvious aging characteristics found by SEM, obviously, the ageing velocity of copper foil -surfaced is higher; The sulfur is found in the powder-like material around the embossment on the surface of copper foils by EDX, which indicates that sulfur is involved in the process of aging.

The feasibility of using laccase to treat oily wastewater was examined. When only laccase was added to the synthetic oily wastewater, the suitable technological conditions were laccase at 3 U/mL, pH at 6.0, a temperature of 30°C, and a reaction time of 6 h for the initial oil concentration of 120 mg/L. Under those conditions, the rate of oil removal was as high as 69%. The effects of Mg2+, Mn2+, Cu2+, and Fe2+ ions in wastewater on the rate of oil removal using laccase were investigated. The results showed that Cu2+and Fe2+ ions obviously inhibited the catalytic performance of laccase under the studied concentration. On the other hand, Mg2+ and Mn2+ ions only had slight effects on the rate of oil removal for the range of concentrations studied. A 95% oil removal rate could be obtained when actual wastewaters were treated using laccase with the additive chitosan under the suitable technological conditions.

The M and NP genes of H5N1 avian influenza virus (A/chicken/Hubei/489/2004) were amplified by RT-PCR from viral RNA, and cloned into pMD18-T vector respectively. The expression plasmid containing the M gene (pHM6-m) or the NP gene (pHM6-np) was then constructed by inserting the M or NP gene into the pHM6 eukaryote expression vector; the constructed plasmid was then sequenced. 32 BALB/c mice (6-week-old) were divided into four groups at random. Three groups of BALB/c mice were inoculated one time the intramuscular route with either 30 μg of plasmid pHM6-m, 30 μg of plasmid pHM6-np or the mixture of plasmid pHM6-m (15 μg) and pHM6-np(15 μg) respectively. A additional group of mice were injected with 100 μl PBS as controls. Two weeks later, all mice were challenged with homologous H5N1 avian influenza virus, and observed in the following 12 days. The survival rates of mice in the pHM6-m group, the pHM6-np group and mixed plasmids group were 62.5%, 25.0% and 50.0%, respectively. Results showed that effective protection could be provided by either pHM6-m or pHM6-np, but pHM6-m provided a better protective effect than pHM6-np.

To enhance the efficiency of the existing freeway system and therefore to mitigate traffic congestion and related problems on the freeway mainline lane-drop bottleneck region, the advanced strategy for bottleneck control is essential. This paper proposes a method that integrates variable speed limits and ramp metering for freeway bottleneck region control to relieve the chaos in bottleneck region. To this end, based on the analyses of spatial-temporal patterns of traffic flow, a macroscopic traffic flow model is extended to describe the traffic flow operating characteristic by considering the impacts of variable speed limits in mainstream bottleneck region. In addition, to achieve the goal of balancing the priority of the vehicles on mainline and on-ramp, increasing capacity, and reducing travel delay on bottleneck region, an improved control model, as well as an advanced control strategy that integrates variable speed limits and ramp metering, is developed. The proposed method is tested in simulation for a real freeway infrastructure feed and calibrates real traffic variables. The results demonstrate that the proposed method can substantially improve the traffic flow efficiency of mainline and on-ramp and enhance the quality of traffic flow at the investigated freeway mainline bottleneck.