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Abstract [Objective] The woody stems of plants are difficult to obtain satisfactory microscopic image in both freehand and paraffin sections due to the high content of secondary vascular tissues and high degrees of lignification of cell walls. Microtome cryostat can section the tissue with a certain hardness. It will be one of the effective tools for the section of plant woody stems. [Methods] Some woody stems with uniform texture and high water content can be sectioned by cryo-sectioning without chemical fixation. For stems with hard wood and less water content, observation was performed after fixation with FAA and other fixation, OCT embedding, (-30) - (-25) ℃ sectioning, and staining with 0.1% toluidine blue staining solution. [Results] For tree or shrub stems with a diameter of less than 6 cm, cryo-sectioning method could be used to quickly obtain complete structure and clear and colorful microstructure images. [Conclusion] The microtome cryostat can be used for microstructure sectioning of woody stems combined with toluidine blue staining, which has the advantage of simplicity, efficiency, and ease of operation.

Objective: To better control the growth of spoilage microorganisms, and ensure the food safety of Xiangwei Luodou dry. Methods: The putrefactive microorganisms in Xiangwei dried tofu were identified by plate scribing method, colony morphology observation, Gram staining, 16S rDNA and ITS sequence. Results: A total of 9 strains were isolated andscreened. KZ2780-3 and KZ2780-4 are Bacillus subtilis, NZ2559-1 is Bacillus cereus, and JZ2559-5 is Bacillusamylolyticus amyloliquefaciens, FZ2559-2 for Klebsiella pneumoniae, SZ2641-5 for Enterococcus faecium, RZ2641-7 for Staphylococcus haemolyticus, BZ2780-1 for Acinetobacter baui, CZ2780-5 for Penicillium citri. Conclusion: The strains causing dry rot of Xiangwei bean are Bacillus subtilis, Bacillus cereus, Bacillus amyloliquefaciens, Klebsiella pneumoniae, Enterococcus faecium, Staphylococcus hemolyticus, Acinetobacter baui and Penicillium citri. The control methods of Xiangwei stewed bean dry are ultra-high temperature instantaneous sterilization technology, plasma sterilization technology, natural antibacterial substances combined with biological preservatives, vacuum packaging, air conditioning preservation and so on.

Abstract [Objective] This study aims to investigate the impact of Streptomyces pactum Act12 broth on growth and physiological characteristics of Medicago sativa seedlings under petroleum stress. [Methods] The effects of different concentrations (0, 1%, 10%, and 100%) of Act12 broth under a petroleum stress level of 3% (W/W ) were examined by determining seedling growth, root morphology, photosynthetic characteristics, osmoregulatory substance content, and antioxidant capacity in M . sativa. [Results] The 3% petroleum significantly hindered photosynthesis and biomass accumulation of M . sativa seedlings, compared to the control group (CK). Moreover, it resulted in elevation in malondialdehyde level, decrease in soluble sugar and soluble protein content, as well as alteration in the activities of superoxide dismutase (SOD) and peroxidase (POD). Compared to the absence of Act12 broth, solutions with low and medium concentrations (1% and 10%) effectively mitigated the toxic effects of petroleum, with 10% Act12 broth exhibiting the most significant effect. The seedlings treated with Act12 broth exhibited significant enhancements in plant height, above-ground dry mass, underground dry mass, stem tolerance index, root tolerance index, total root length, root surface area, root volume, and number of root tips. Additionally, the level of MDA was decreased by 42.49% and 56.45%, soluble sugar was increased by 79.25% and 89.83%, while soluble protein was increased by 167.63% and 256.15% in the above-ground and underground parts, respectively. Moreover, SOD and POD activity were increased by 35.81% and 57.33%, respectively. [Conclusion] The fermented liquid with low/medium concentration effectively modulates antioxidant enzyme activity and osmotic regulation ability of seedlings, resulting in reduced MDA content, enhanced photosynthesis ability, increased biomass, and eventually alleviates the inhibition effects of petroleum stress on seedling growth.

The hot-rolled Al-Zn-Mg-Cu system aluminum alloy was treated with single-stage solution，low temperature-long term & high temperature-short term and low temperature-short term & high temperature-long term，double-stage solution quenching systems. The effects of different solution methods on the structure and properties of Al-Zn-Mg-Cu system aluminum alloy were systematically compared and analyzed by OM，SEM，DSC，EBSD and other technical means，as well as conductivity testing methods. The results show that the selected solution quenching system will not cause the structure to overheat，and can fully dissolve the eutectic second phase of the low melting point in the structure. When 473 ℃/20 min+477 ℃/40 min two-stage solution quenching system is selected，the plate has the best solution effect and the lowest conductivity，which is 27.60%IACS，and the recrystallization degree of the structure is less than 50%. There are {112}〈111〉，{011}〈211〉，{123}〈634〉 deformation texture and {001}〈110〉 shear texture in the structure.

Objective To investigate the correlation between the expression of Hsa_circ_0026352 and the clinical characteristics of breast cancer(BC) patients, to evaluate the value of Hsa_circ_0026352 as a diagnostic marker of breast cancer. Methods Human circRNA microarray was used to screen the different expression of circRNAs in BC tissues. qRT-PCR was used to verify the expression of Hsa_circ_0026352 in BC tissue and peripheral blood. CircRNA structure were performed by circPrimer1.2 software. T-test, ANOVA analysis, curve regression analysis and ROC curve analysis were performed to determine the diagnostic values of Hsa_circ_0026352. Results Hsa_circ_0026352 was significantly down-regulated in both breast cancer tissues and peripheral blood (P < 0.01). The AUC of Hsa_circ_0026352 were 0.881 in tissues and 0.826 in peripheral blood (both P < 0.01). The relative expression of Hsa_circ_0026352 in peripheral blood of BC cancer patients was negatively correlated with CA153 level (P < 0.05). The AUC of Hsa_circ_0026352 in peripheral blood of patients with ER positive, early stage breast cancer and breast neoplasm metastasis were 0.710, 0.771 and 0.722 (all P < 0.01), respectively. Conclusion Hsa_circ_0026352 could be a novel predictive biomarker for diagnosis of BC.

With the increasing reliability requirements of electronic products, the use of failure physics methods to identify potential weak points in product design has attracted much attention. In this paper, the theory of failure physics and reliability simulation analysis method are used to analyze the reliability of electronic controller. By establishing a digital prototype model of electronic controller, the corresponding stress analysis and fault prediction are conducted to evaluate the mean time to first failure（MTTFF）reliability index of the electronic controller, and optimize the design based on the weak links found in simulation results. It is indicated that the difference between the reliability results and the theoretical calculation results are not significant, and can be used as a basis for evaluating the reliability indicators of models, reducing the cycle and cost of using physical prototypes for reliability testing. At the same time, the optimization and improvement have significantly improved the reliability design of the electronic controller, laying a theoretical foundation for subsequent model reliability evaluation and design.

[Objective] To analyze the scale-dependent relationships between daily sediment yield and key environmental factors and to explore effective prediction method to cope with the prediction challenges caused by the complexity of sediment transport mechanisms and the nonlinearity of hydrological processes. [Methods] Employing the Composite Ensemble Empirical Mode Decomposition with Adaptive Noise (CEEMDAN) approach, we analyzed the multi-temporal scale variability characteristics between daily sediment yield and five potential influencing variables (flow rate, precipitation, average temperature, potential evapotranspiration, and NDVI) in the controled regions of four hydrological stations in the Fu River basin of Southwest China from 2013 to 2018. Interactions between daily sediment yield and related variables at different temporal scales were identified, upon which predictions of daily sediment yield were predicted. [Results] The CEEMDAN method successfully decomposed the daily sediment yield and its potential influencing variables into 10-11 intrinsic mode functions (IMFs) and residual item, revealing the significant changes of the daily sediment yield at different temporal scales ranging from 3 to 730 days. After decomposition, daily sediment yield showed significantly enhanced correlation with howrate and precipitation across all temporal scales, whereas temperature, potential evapotranspiration, and NDVI were primarily significantly correlated with long-term scale sediment yields. By using stepwise multiple linear regression to predict the daily sediment yield, the prediction performance of the model is significant, and the R2 values exceeds 0.55 at all stations. [Conclusion] The CEEMDAN method effectively revealed the scale dependency between sediment yield and its influencing variables, offering a new perspective for understanding the dynamics of river sediment transport.

Background Sleep duration of the undergraduates are closely related to their health, but there is no conclusion about the best sleep duration for undergraduates. And there is a lack of research about the dose-response relationship between sleep duration and Traditional Chinese Medicine (TCM) constitution. Objective To explore the relationship between sleep duration and TCM constitution for undergraduates, and to provide reference for their health education about sleep duration. Methods This study used a combination of purposeful sampling and snowball sampling methods to conduct on-site questionnaire survey on students from 143 universities including Beijing University of Chinese Medicine, Harbin Institute of Technology (Weihai), Peking University, Northwestern Polytechnical University from January to June 2019. We used the Constitution in Chinese Medicine Questionnaire of 41-item (CCMQ-41) to assess the TCM constitution of undergraduates, and used a self-designed questionnaire to measure socio-demographic information and lifestyle behaviors. This study used the restricted cubic spline fitting multiple linear regression model to analyze the dose-response relationship between sleep duration and TCM constitution with taking sleep duration as the independent variable and TCM constitution score as the dependent variable, and controlling for related confounding variables. Results This study collected 1 003 valid questionnaires. The response rate was 98.2%. Pearson correlation analysis showed that the sleep duration was negatively correlated with the score of qi depression (r=-0.067, P=0.034). After controlling for confounders, multiple linear regression analysis showed that there was no linear relationship between sleep duration and TCM constitution scores (P>0.05). The dose-response relationship analysis showed that the highest point of gentleness score and the lowest point of biased constitutions score (except specific diathesis) had a sleep duration of about 8 h. When the sleep duration was >8.5 h, the gentleness score showed a tendency to decrease, and the scores of qi deficiency and qi depression had a tendency to increase (P

Objective·To establish an in vitro culture model mimicking tumor microenvironment using hydrogel microspheres and fresh primary pancreatic cancer cells.Methods·The morphological distribution of the hydrogel microspheres was recorded, observed and photographed under an inverted fluorescence microscope. The diameter of the microspheres was calculated by Image J, and the particle size distribution map was obtained by statistics. Renal epithelial cells (293T), pancreatic cancer cells (8988), and normal pancreatic epithelial cells (HPNE) were grown in DMEM complete medium, and passaged when the cells were 80%‒90% confluent. 293T cells were cultured in DMEM medium and microsphere extract, and the proliferation curve of 293T cells cultured in the two mediums was detected by CCK-8 method to explore the biocompatibility of hydrogel microspheres. Fresh pancreatic tumor tissue was cut in the ultra-clean workbench, and pancreatic cancer tumor tissue was lysed by hyaluronidase and collagenase Ⅰ, and digested into single cell with interval shaking in a 37 ℃ water bath. The hydrogel microspheres and pancreatic cells were co-cultured in DMEM complete medium for 3 d, 1/2 of the cells were fixed with 4% paraformaldehyde, and stained with phalloidin and DAPI, and the morphology and cell distribution of the microspheres were observed under a common fluorescence microscope. The remaining 1/2 cells were used for suspension and adherent cell counting. The hydrogel microspheres and primary cells were co-cultured in the medium for 7 d, and the cell composition in the established culture model of in vitro pancreatic cancer primary cells based on the hydrogel microspheres was observed by immunofluorescence method. The pancreatic cancer tissue was embedded in paraffin, followed by paraffin tissue sectioning, hematoxylin and eosin staining of the tissue section, and observation of the pancreatic cancer tissue structure with a microscope.Results·The size of the hydrogel microspheres was uniform, and the diameter of the microspheres was about 200 μm. The proliferation curve of 293T cells showed that the hydrogel microspheres had good biocompatibility. The co-culture experiments of hydrogel microspheres and pancreatic cell lines showed that the surface of hydrogel microspheres had strong cell affinity, which could provide support points for pancreatic cells to adhere to the surface of the microspheres and to grow normally. Through co-culture of hydrogel microspheres with fresh pancreatic cancer cells, a 3D culture model of pancreatic cancer cells in vitro was successfully established. Composition of cell types in this model was similar to that in the corresponding primary tumor tissue, which included pancreatic ductal epithelial cells, tumor stem cells, endothelial cells, fibroblasts and other cells.Conclusion·The in vitro 3D culture model of primary pancreatic cancer cells based on hydrogel microspheres has important characteristics of pancreatic cancer tumor microenvironment.

It is of great practical significance to comprehensively recover aluminum from the low-grade aluminum ore wet processing process to realize recycling or high value utilization of low-grade aluminum-containing minerals. The high aluminum and iron leaching solution obtained by sulfuric acid leaching of low-grade aluminum-containing anatase ore was used as the research object, and high-purity Al2O3 was prepared by Crystallization of ammonium aluminum sulfate--Removal of iron with resin adsorption--Calcination combined process. The results show that under the condition of initial concentration of aluminum ion of 0.70 mol/L, NH4+/Al3+ molar ratio of 1.2, crystallization end point temperature of 20 °C, and stirring speed of 300 r/min for 30min, NH4Al(SO4)2 ⋅ 12H2O crude product with a purity of 95.31% was obtained. The aluminum recovery rate was 88.19%, and the iron content was 1.39%. Then, the crude NH4Al(SO4)2 ⋅ 12H2O product was subjected to iron removal by two recrystallizations and primary resin adsorption, and finally calcined at 1 300 °C to obtain Al2O3 with a purity of 99.99%. [ABSTRACT FROM AUTHOR]

Magnetic remote-reference is the most practical noise suppression method in magnetotelluric data processing.In actual audio-frequency magnetotelluric (AMT) sounding observation, usually the "one with three" or "one with four" acquisition method is used, i.e., acquiring magnetic field of only one site and simultaneously acquiring electric field of multiple sites, without magnetic field data for remote-reference processing.The natural electro-magnetic field in the 5~1 kHz "dead band" range of signal strength is weak, resulting in the impedance in this band to have "outlies".In this paper, we found that the impedance estimated by using the local magnetic field and the local electric field as the reference in the "dead band" will be "upward" and "downward" biased respectively, while the electric field as the remote-reference channel can significantly improve the impedance quality in the "dead band".After processing the measured data of different reference distances, it is found that the effect of the electric field remote-reference processing is better than that of the local magnetic field and the local electric field.And the effect is comparable to that of magnetic field remote-reference.This has practical implications for AMT data processing.

The domestic and overseas technical advance about reducing ballistic temperature coefficient of gun propellant charge, including surface compensation technic such as mechanical flattening technology, coating technology, surface coated double base (SCDB) technology, extruded impregnated (El) technology, extruded composite low sensitivity (ECL) technology and so on, were reviewed. The burning rate of low temperature coefficient (LTC) gun propellant can be kept basically consistent at different temperatures by optimizing its configuration, resulting in decreased ballistic temperature coefficient of gun propellant charge. Electrothermal-chemical launch technology can reduce ballistic temperature coefficient of gun propellant charge significantly by adjusting input energy to compensate the decrement of burning rate of gun propellant. Combined with the basic principle of reducing ballistic temperature coefficient of gun propellant charge, the regulatory mechanism of reducing ballistic temperature coefficient of gun propellant charge by using different technological approaches is summarized. Based on the above discussion, the researches on ECL gun propellant and SCDB gun propellant should be carried out in the future. And the research on the interaction mechanism of plasma and gun propellant and the study on the miniaturization of power supply should be further strengthened with 62 references. [ABSTRACT FROM AUTHOR]

The helicopter emergency floating system is one of the main equipments for helicopter lifesaving at sea. The reliability of its sensor module is analyzed, it is very important to ensure the safe operation of helicopter emergency floating system and reliable triggering in the process of falling water. Based on the systematic understanding of k/n(G) voting system composed of different types of units, Monte Carlo (MC) simulation platforms of sensor module under different logic relations are built by using Matlab/Simulink and the corresponding simulation and theoretical calculation are carried out. The results show that it is feasible and effective to apply Monte Carlo method to reliability analysis of sensor module. According to the results of functional hazard analysis and reliability analysis, the 3/5 voting system is more suitable for the sensor module of the helicopter emergency floating system. This provides a technical route for the logical relationship selection and reliability design of similar modules.

The aim of our study is to estimate the effects of inoculation with arbuscular mycorrhizal fungi and fertilization on rice quality. Rice quality was estimated for inoculated and non-inoculated rice grown in both fertilized and non-fertilized paddy fields. It was found that in non-fertilized paddy fields there was a negative effect of inoculation on rice processing and appearance quality but no significant effect on cooking, tasting and nutrition quality. In addition, fertilization improved rice processing and cooking quality whereas no significant effect was found on appearance, tasting and nutrition quality. Finally, the interaction between inoculation and fertilization improved appearance, cooking and tasting quality and guaranteed the Fe and Zn content of rice. In conclusion, interaction between AMF inoculation and fertilization plays a vital role in impioving rice quality. [ABSTRACT FROM AUTHOR]

Low temperature inhibits the performance of nitrogen removal efficiency during the biological treatment of municipal wastewater. Therefore, the effluent could hardly meet the emission standard. To enhance the performance of nitrogen removal at low temperature, a psychrotolerant aerobic denitrification consortium by fast enrichment and domestication was obtained, which could remove the ammonia, nitrate and organic matter simultaneously and efficiently in aeration environment under 10 °C. The results showed that the removal efficiency of ammonium and total nitrogen by bioaugmentation was improved by 10.31%-16.89% and 25.07%-32.44%, respectively. It made the effluent quality meet the grade lA level of national discharge standard. After bioaugmentation terminating for 10 days, the remained consortium could still improve the reactor that the effluent of ammonium, nitrate, total nitrogen and CODCr concentrations was decreased about 2.43, 3.07, 6.02 and 3.63 mg/L, respectively. The results indicated that bioaugmentation performed well and persistently. [ABSTRACT FROM AUTHOR]

To put forward a fenton-like system based on a new type of Fe3O4 magnetic nanoparticles catalyst, Fe3O4 magnetic nanoparticles were prepared using chemical co-precipitation, and their surface was modified with tetramethyl ammonium hydroxide (TMAH). The catalyzed degradation of phenol by Fe3O4-H2O2 Fenton-like system was investigated, including the effect of catalyst dosage, H2O2 dosage, pH value and reaction time on the removal of COD and volatile phenol. The results showed that the mean size of the Fe3O4 nanoparticles is 30 nm and they show a good disparity between 20 and 100 nm. Three different doses of TMAH coated catalysts after ultrasonic pretreatment, revealed almost the same treatment efficiency of 50 mg/L phenol (112 mg/L COD equivalent) under the room temperature (13 °C). Under the condition of 0.8 mmol/L catalyst dosage, 2.0 mmol/L H2O2 dosage, pH 4.5 and the reaction time of 180 minutes, the highest COD removal efficiency was 72%; while under the condition of 0.4 mmol/L catalyst dosage, 2.0 mmol/L H2O2 dosage, pH 4.5 and the reaction time of 90 minutes, the removal rate of volatile phenol was close to 100%. 3# Fe3O4-TMAH(2 mL) catalysts revealed optimal reuse efficiency, the removal rate of COD were 73%,29%,28%,26%, the removal rate of volatile phenol were 100%, 84%, 67%, 54%. The Fenton-like system has the advantage of no redundant excess sludge producing, and the magnetic catalyst can realize quick separation and recycling under the action of outside magnetic field. [ABSTRACT FROM AUTHOR]

According to the characters of HABS industrial wastewater of high pH, high COD and high concentration of sulfite, a pilot reactor with catalytic oxidation-Fenton combined treatment process was built, and the pilot scale experiments were employed to discuss the optional parameters. A pilot scale is 5 t/d. After optimized, the optimal optional parameters in catalytic oxidation stage were pH 8, aeration rate 50 m³/h, HRT 90 min. The optimal optional parameters in Fenton stage were dosage of H2O2 (30%) 1. 00 mL/L. The effluent quality can meet the first class requirements of Sewage Discharge Standard in GB8978-1996, which suggests the process is economical and feasible. [ABSTRACT FROM AUTHOR]

To realize the stable and efficient operation of biogas digester in cold region, a combined regulation technique of microbial community should be established. The microbial community in the largest full-scale digester of Hailin Farm was investigated using 454 pyrosequencing technology and PCR-DGGE. The massively parallel sequencing technology was used to measure bacterial diversity of biogas slurry during a stable operation. A total of 1297 sequences were obtained, and the dominant bacteria were Firmicutes, Bacteroidetes and Proteobacteria, which accounted for 46.39%, 21.41% and 18.98%, respectively. At genus level (the relative abundances > 5. 0%), Proteiniphilum, Spirochaeta and Wolinella were the abundant taxa. The diversities of methanogen were analyzed using PCR-DGGE, and the detected archaea were Methanocorpusculum sp., Methanosaeta sp., Methanobacterium sp. and Methanosarcina sp.. Notably, the methane produced by acetoclastic methanogens, and dominant fermentative bacteria during the hydrolysis and acidogenesis were detected form animal digestive system. [ABSTRACT FROM AUTHOR]

To improve the growth and survival rate of plants in vegetation-growing concrete, we chose two kinds of arbuscular mycorrhizal fungi, Glomus mosseae and Glomus intraradices, to study the effect of pure fungi, mixed bacteria on Poa pratensisl. cv. BALIN in vegetation-growing concrete. The results show that: The single application of Glomus mosseae (GM) can obviously improve the infection rate to 43.27%. Poa pratensis has stronger dependence on Glomus mosseae and mixed fungicides (MI) with little difference than Glomus intraradices (GI). The plant height and aboveground biomass with MI treatment can be increased by 15.8% and 20% respectively. Mtreatment can increase the underground biomass by 48% higher than any other treatment. M treatment can significantly improve the proline and soluble sugar contents by 45.4% and 27.7% and reduce the malondialdehyde content (MDA) by 14.7% which can enhance the plant stress-resistance. M treatment can make the plants get the highest CO2 assimilation and water use efficiency (WUE), enhancing Poa pratensis' ability of using the light and water and improving better growth of plants. Glomus mosseae is the best choice to improve vegetation-growing concrete. [ABSTRACT FROM AUTHOR]

To optimize the fermentation parameter of Klebsiella. sp, orthogonal experiments were used to quantify the degree of the fermentation parameters of flocculant-producing bacteria MFX on the flocculation rate and the yield, which indentified temperature, shaking revolution and pH value as the input of neural network, flocculation rate and yield as the output of neural network, and then a training sample was designed. After repeat training, a prediction model with high accuracy and small error was established by which the optimum fermentation conditions: the temperature of 33 °C, the stirring speed at 141 r/min and pH value of 7.90, were obtained. Meanwhile, the actual flocculation rate and the yields were 92.67% and 2. 180 9 g/L, respectively. The flocculation rate increased 4.08%, and the yields of bio-flocculant increased 14.36%, which improved the yield of bio-flocculant. The model was used to predict the fermentation process of flocculant-producing bacteria F + in the fermenter, the simulation error was small, which was the basis for the prediction and control of industrial fermentation process. [ABSTRACT FROM AUTHOR]

To overcome the drawbacks of high bulk density and bad applicability, in this study, straw ash was used as an additive to make unburned ceramsite which could be applied to sewage treatment. This method not only broadened the application of the unburned ceramsite and promoted unburned process, but also provided an economical and rational way to dispose fly ash and straw ash from power plant. The activity-excitation mechanism of fly ash, the function of primary components and the phase composition of ceramsite were studied in this research. The optimum process parameters were; 5% NaOH solution pretreat fly ash, and the ratio of the components were fly ash of 58. 11% , calcium oxide of 4. 84% , cement of 29. 05% and straw ash of 8% ; The main characteristics index of ceramsite were shown as follows: bulk density of 785 kg/m³, specific surface area of 11. 1 m²/g, broken rate of 2. 3%. The ceramsite was tested on leaching toxicity and basic properties, and the results indicated that it was a proper way to make functional ceramsite of good property used in sewage treatment with straw ash as an additive raw material, and it achieved the purpose of economic energy conservation and waste treating. [ABSTRACT FROM AUTHOR]

The influences of different fixed ways of polyurethane on the purification performance of wastewater treatment in biological contact oxidation were discussed, the polyurethane was put into biological contact oxidation by up-floating, sinking and general up-floating general sinking respectively, the relationship between microbial community structure and purification performance was analyzed. The results showed that polyurethane fixed by general up-floating general sinking could most efficiently remove pollutants, the purification rate of COD and NH4+ -N were 90% and 94% ; the attached microbial populations were with the largest number, the highest diversity, the strongest activity and the most reasonable function in this way. Therefore, the purification performance was affected by the fixed way of polyurethane in biological contact oxidation and the general up-floating general sinking was the most effective fixed way. [ABSTRACT FROM AUTHOR]

The release rate of soil CO2 and its factors were measured with CIRAS-2 portable photosynthesis system, then their relationship was analyzed to investigate the influences of the additional nitrogen fertilizer, phosphate fertilizer and arbuscular fertilizer on characteristics of soil CO2 release in paddy. The results showed that: (1) The addition of nitrogen fertilizer resulted in soil CO2 release rate rising by 97.73% in 0 cm layer, and dropped by 39.93% and 31.36% in 10 cm and 20 cm layer, respectively. (2) While there was no significant difference between soil CO2 release rates after the addition of phosphate fertilizer and of CK in 0 cm layer, the rate dropped 33.84% in 10 cm layer and rose 48.03% in 20 cm layer. (3) The additional arbuscular fertilizer had no significant influence on all three layers. (4) The related coefficients of soil CO2 releasing rates and their factors in the same layers were affected by the fertilizer-modes, and its impact became lighter with the increasing of depth. Compared with nitrogen fertilizer and phosphate fertilizer, mycorrhizal fertilizer had no significant influence on the soil CO2 release. [ABSTRACT FROM AUTHOR]

The Fe/C micro-electrolysis and Fenton combined process was used to solve the high yield organic CLT acid wastewater in our country. The influence factors of pH, reaction time, ratio of iron and coke, H2O2 dosage and reaction time of H2O2 were investigated. The results show that when the influent COD is 28.1 g/L to 34.5 g/L, pH is 2.5, ratio of iron and coke is 2:1 and the reaction time is 60 min, the removal rate of COD by ferric-carbon micro-electrolysis is above 30%. For treatment with the Fenton when the H2O2 (30%) dosage is 0.15 mol/L, the reaction time is 60 min and the temperature is 20 to 30°C, the removal rate of COD reaches more than 43%, B/C ratio of wastewater increases from 0.08 to 0.43. [ABSTRACT FROM AUTHOR]

To explore the COD degradation characteristics of Jiamusi section at Songhua River, water mass tracing and Rhodamine-B tracing were used to investigate the COD model of the normal river flow season and icebound season of Jiamusi section. The corresponding characteristic parameters were identified, the diffusion characteristics of river water quality of the Jiamusi section were discussed, and the validity of the model was verified by the water quality mathematical model and water mass tracing. The results showed that by Rhodamine-B tracing, the transverse diffusion coefficient of the Jiamusi section was 0.41 m²/s, and the longitudinal diffusion coefficient is 43.51 m²/s. The COD attenuation coefficient K(20) = 0.188; the COD model parameters were corrected at any temperature K(T) = 0. 188 x 1. 109 8T - 20. The relative error of the measured results and the simulation results were both within 10%, which proved that the COD model and the corresponding parameters were effective. [ABSTRACT FROM AUTHOR]

To explore the effect of different AMF microbial inoculum on the growth of Trifolium repens lawn, we chose two kinds of widely used strains, Glomus mosseae and Glomus intraradices, to study the promoting effect of single bacterium, mixed bacteria on Trifolium repens respectively. The results show that: Simple infliction of Glomus mosseae could obviously improve the infection rate to 53.84%; Trifolium repens has evident dependence on fungicides especially on mixed fungicides. Besides, the dependence of plant aerial parts are obviously higher than underground ones; AMF has apparent promotion on the growth rate of Trifolium repens. The mixed fungicides are better than single ones, the growth rate of plant height, the overground and underground" biomass liveweight could be improved by 40.7%, 76.6%, 35.7% respectively; AMF could effectively enhance the Trifolium repens' absorption capabilities of nutriment in rhizosphere soil, improve the utilization rate of hydrolysable nitrogen, available phosphorus to 51.6%, 48%. Hydrolysable nitrogen is the main inhibiting factor restraining fungicides promotion on the growth of Trifolium repens with microbial inoculum, the phosphatic fertilizer is not needed, but a few nitrogen fertilizer is. [ABSTRACT FROM AUTHOR]

Water resources ecological footprint can directly reflect the pressure of human social and economic activities to water resources, and provide important reference for the rational utilization of water resources. Based on the existing ecological footprint models and giving full consideration of the water resources need of urban ecological system, this paper established a new calculation model of urban water resources ecological footprint, including domestic water account, process water account, public service water account, and ecological water requirement account. According to the actual situation of Shenyang City, the key parameters of the model were determined, and the water resources ecological footprint and ecological carrying capacity of the City were calculated and analyzed. From 2000 to 2009, the water resources ecological footprint per capita of the City presented an overall decreasing trend, but still had an annual ecological deficit. As compared to that in 2000, the water resources ecological footprint per capita was decreased to 0. 31 hm2 in 2005, increased slightly in 2006 and 2007, and remained stable in 2008 and 2009, which suggested that the sustainable utilization of water resources in Shenyang City had definite improvement, but was still in an unsustainable development situation. [ABSTRACT FROM AUTHOR]

To control agricultural non-point source pollution, the cleaning biological fertilizer and chemical fertilizer were used together to raise nitrogen use efficiency. The growth and production of rice under the conditions of single application of nitrogen fertilizer (N), single application of biological fertilizer with Glomus mosseae as the subject(M) and joint application of nitrogen fertilizer and biological fertilizer(NM) were studied, and the results reveal: (1) The application of nitrogen and G. mosseae (NM) makes rice reach the highest net photosynthetic rate, and increases by 4.5% and 5.0% more than N and M treatment, respectively. (2) The nitrogen fertilizer can increase the aboveground biomass by 22.8%, the biological fertilizer can increase the underground biomass by 41.5% significantly (P < 0.05) , and NM treatment can promote both the above-and under-ground biomass (37.0% and 35.0%, respectively). (3) The NM treatment increases rice yield by 4.8% more than traditional nitrogen fertilizer management. Therefore, mycorrhizal infection to the rice can effectively improve the efficiency of resource utilization, growing and producting capacity. [ABSTRACT FROM AUTHOR]

Microbial culture-independent technology, such as DNA fingerprinting technology, pyrosequencing, molecular hybridization technology, metagenomics, metatranscriptomics, metaproteomics, metabolomics and so on, has developed rapidly and been applied extensively in many fields, which could assist in the identification of microbial species from natural or anthropogenic environment rapidly and accurately. The microbial culture-independent technology has provided crucial in-sights for revealing microbial community structures, functions and remediation mechanism during bioremediation process and improving the detection efficiency of bioremediation. This review is mainly focused on the advanced applications of molecular biology and microbial culture-independent technology of "-- omics" in gauging microbial community structures, functions and dynamics at contaminated areas. [ABSTRACT FROM AUTHOR]

With different fertilization, the photosynthetic rate of rice was measured, then the distribution and yield components were analyzed to investigate the influences of single mycorrhizal fertilizer and the mycorrhizal fertilizer mixed chemical fertilizer on rice yield. The results showed that: 1 ) The usage of single mycorrhizal fertilizer increased the storage capacity and the photosynthetic rate of rice, making rice yield increase by 29.27%, while there was no difference in distribution of dry matters. 2) The photosynthetic rate of rice was improved by the mycorrhizal nitrogen fertilizer, moreover, the proportion of dry matter to the rice seeds raised, and rice yield increased by 41.37%. 3) The photosynthetic rate of rice was enhanced by the mycorrhizal phosphate fertilizer and the mycorrhizal nitrogen and phosphate fertilizer; there was no difference in distribution of rice dry matter; the rice yield increased by 19.10% and 17.48%, respectively. The usage of single mycorrhizal fertilizer and the mycorrhizal nitrogen fertilizer can effectively improve the rice yield, but it needs further research to touch the effectiveness of the other fertilizer-modes. [ABSTRACT FROM AUTHOR]

To investigate the residues and pollution sources of DDT and HCH in the Xiao Qing River sewage irrigated wetland and study the distribution.of pollutants (DDT and HCH) along the vertical soil profile, soil samples were pretreated by Soxhlet extraction and silica gel purification, and the HCH and DDT content were analyzed by GC - MS. The results show that the concentrations of ΣHCHs and ΣDDTs in the soils range from ND -0. 225 µg/kg and ND - 1. 204 µg/kg respectively, with the mean concentrations of 0. 042 µg/kg and 0. 204 µg/kg. The concentrations of DDTs and HCHs are below the national soil environmental quality standards (GB 15618-1995) , which are at a low residue levels. The HCH. residues in wetlands without irrigation are caused mainly by historical pesticide using and there is few pollutions generated recently. DDT contamination of wetlands exists mainly in the form of DDE, that is due to historical pesticide using. Sewage irrigation reduced soil residues of DDT and HCH, with average reduction rate of 67. 16% and 78%. The HCH residues are higher than DDT residues at the same point. The DDT contents drop sharply along the soil profiles, and the HCH contents change. irregularly along the soil profiles. [ABSTRACT FROM AUTHOR]

Extraction of metagenomic DNA from environmental sample was the main restrictive factor for the metagenomic sequencing. Three different extraction methods were used and compared in this study. The results indicated that the metagenomic DNA obtained from the activated sludge by Liquid Nitrogen Grinding + DNA Extraction Kit was the best sample due to the largest information and best quality, and D (260/280 nm) was between 1. 69 -1. 72. During the sample preparation for the next generation sequencing, D (260/280 nm) of the metagenomic DNA reached to 1. 83 after purification, which met the requirement of library construction. After the sequencing by Solexa Genome Analyzer System, the results showed that the forward sequencing of these two samples was successful, and the high quality data was about 90. 8%, which could be used for assemble. [ABSTRACT FROM AUTHOR]

To improve demulsifying property, the original biodemulsifier-producing bacterium, Bacillus mojavensis XH1, was mutated and bred by the combined treatment method using UV irradiation and niitrosoguanidine (NTG). A high efficient biodemulsifier-producing mutant XN5 with the better stability was obtained after continuous passages. The optimal cultural conditions were as follows: the mixture of 10 g/L glucose and 4 % liquid paraffin is the carbon source, the mixture of 4.0 g/L NH4Cl and 1.0 g/L yeast extract is nitrogen source, pH =6. 5 , the rotating rate is 140 r/min and the incubated time is 24 h. The 12 h and 24 h demulsification ratios of the mutant XN5 were 94. 17% and 98. 67% , which were 64. 81% and 15. 12% higher than that of the original strain XH1, respectively. [ABSTRACT FROM AUTHOR]

To find a method of microbial immobilization which was efficient, fast and applied to biomass carrier mycelial pellet, bacteria JH -9 were immobilized onto mycelial pellet formed by Aspergillus Y3. And the characteristics and internal structure of two different immobilization methods were compared. The simultaneity culture immobilization method could immobilize more bacteria and with little time with same bacteria inoculation count. Moreover, the volume and quantity of combined mycelial pellets formed by simultaneity culture immobilization method were bigger than that by adsorption immobilization method, and its diameter ,weight and relative density were smaller. To immobilize with the same method, the size and volume of combined mycelial pellets were in direct proportion to the inoculation count of engineering bacteria, whereas its weight and relative density were opposite. Bacteria were immobilized and grew on each mycelium of combined mycelium pellets formed by simultaneity culture immobilization method. [ABSTRACT FROM AUTHOR]

In this paper, 16 denitrifying phosphate --accumulating organisms (DNPAOs) were isolated in the special medium from the anaerobic/aerobic/anoxic SBR reactor, and the most efficient DNPAOs called Q -- hrb05, was screened by a phosphate uptake experiment, where nitrates were denitrified to gas and through inspection of the poly -- P. Strain Q -- hrb05 was identified by 16S rDNA gene analysis, and the accession number of 16 S rDNA gene sequence of strain Q -- hrb05 in GenBank was GU214826. The result showed that the strain Q -- hrb05 belonged to Bacillus sp, of which the homology could reach to 99%, that also corresponded to the result of biochemical features. The average phosphorus uptake rate of strain Q -- hrb05 was at 85% within 12 hours, and it had the denitrification capacity in the aerobic condition. It could be found that the phosphorus uptake rate was related to the content change of PHB. Under anaerobic condition, the maximal P -- release rate was 66%, which could reach to 12% of the dry cell weight. The P -- uptake rate was 92% with the decreasing of PHB content. [ABSTRACT FROM AUTHOR]

A three - way hybrid was obtained using early mature spring - type Huayou 8 (H8) , Legency and late mature semi - winter line 020010 of Brassica napus. Series of new germplasms with large seed trait, i. e. thousand seeds weight over 5. 0g, were discovered from DH lines of the hybrid. Among them, the agronomic traits of 5 lines were studied between 2007 - 2009. They showed stable large seeds property and higher yield potential with the variation of thousand seeds weight less than 10% to 15% during these years. The yield of DL01 and DL02 were 30. 6% and 20. 4% higher than a hybrid cultivar Yunyouza 2. [ABSTRACT FROM AUTHOR]

To reveal the relationship between microorganism and pollutants' degradation in the stability system of the municipal wastewater treatment plant, the dynamic monitoring of microbial community structure and metabolic activity of the stable operation biological system in biological wastewater treatment plant was carried out using the denaturing gradient gel electrophoresis (PCR - DGGE) and Biology Technology. The results showed that the average removal efficiency of effluent Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed. and TN was more than 84.4%, 84.7% and 59.8%, respectively. The microbial community structure was stable in the different sites of biological system in the same season, and the ecological niche of predominant functional species including Bacillus , Pseudomonas, Aeromonas was stable. As the temperature increased in spring, the quantity and diversity of population increased significantly. Meanwhile, metabolic activity strengthened in biological system, which could improve the removal rates of pollutants. It is feasible to use the two methods to monitor the changes of microbial community structure of biological system in a wastewater treatment plant at low temperature. [ABSTRACT FROM AUTHOR]

The use of microbial de-emulsifier is limited for its low de-emulsification activity, instability and sensitivity to environmental factors. To solve this problem, two superior strains ( Bacillus mojavensis , Bacillus subtilis ) were cultured in a mineral salt medium to obtain a microbial compound de-emulsifier with high capability of de-emulsification. The cell culture could demulsify the O/W model emulsion completely in 48 h at room temperature. Comparing with that of the single strain culture, the fermentation process of the mixed culture was shortened more than 6 h. With less addition volume, the mixed culture showed higher de-emulsification activity and stability. The microbial compound de-emulsifier kept high de-emulsification activity in the emulsion with different pH value ranged from 3 -7. Thermostability was detected. When the emulsion temperature varied from 20 - 120 °C, changing rate of the oil drain rate was under 15%. After the strains were mixed cultured, the metabolites produced during the fermentation process still took the main function of de-emulsifiction. The supernatant remained 87% de-emulsification ability of the cell culture while the bacterial cells could hardly break the emulsion. Comparing with the widely used chemical ones, the microbial compound de-emulsifier has almost the same effectiveness in dealing with the oil-bearing waste water from Daqing oilfield. Compounding microbial de-emulsifiers is an effective way to enhance their demulsification abilities. [ABSTRACT FROM AUTHOR]

To investigate the mechanism of simultaneous nitrification and denitrification (SND) and promote the efficiency of SND system, by using the domesticated efficient SND sludge, the effects of organism, DO and temperature on the SBR reactor were studied. The experiment results showed that, when the temperature was 25 -30 and pH was 7 -9, the nitrate -nitrogen removal was preferably; when C/N rate varied between 1:1 - 8: 1, COD concentration, ammonia nitrogen removal rate and TN removal rate decrease with the increasing of C/N rate. Dosing organic compounds in twice can enhance the aerobic denitrification effect. When aeration volume varied from 0. 12 to 0.80 L ⋅ min -1 , ammonia nitrogen removal rate increased first and then kept approximate constant with the increase of aeration volume, finally became stable at 99.8%. TN removal rate increased first to the highest at 95.52%, then decreased, when aeration volume was 0. 2 L ⋅ min -1, and COD was stable above 91%. The influence of aeration rate on the COD removal is not distinct. The best effect will be achieved if the system temperature is 25 -30 ° C, C/N rate is 1.5: 1, aeration volume is 0.2 L ⋅ min-1 , pH is 7 -9 and the dosing of organic compounds is in twice. [ABSTRACT FROM AUTHOR]

To effectively protect drinking water resources, a scientific assessment on site selection of River drinking water resources was carried out. Twenty - eight key factors including law, environmental quality, water resources assurance and environmental risk were selected, and based on analytic hierarchy process (AHP), a mathematical model of assessment system was established. The weight of factors was defined by the method of document data and expert questionnaire, and these weights were synthesized under single criterion. These influence factors were classified and quantized with laws, technical standards and statistical data. According to the calculation of factor scores and weights, the recommendations of site selection can be given. [ABSTRACT FROM AUTHOR]

Low temperature anaerobic digestion, that is how to convert biomass waste into biogas effectually in low temperature, is the key technique which restricts biogas application in northern rural. This paper mainly states the current biogas application technique and existing problem, and suggests some new research theory and technology. Additionally, microbial molecular ecology and proteomics are used to ensure process of biogas production stabilization and the research development in the future are discussed. [ABSTRACT FROM AUTHOR]

To further promote the water pollution control of Northeast China, to ensure the water environmental safety of Songhua river and Liaohe river, and to accelerate the harmonious development of economy, society and environment in Northeast China, the performances of 32 typical municipal wastewater treatment plants (MWWTPs) located in 13 key cities of Liaoning, Jilin and Heilongjiang were investigated and analyzed. General problems generated in the operation and management of these MWWTPs were found out, and the corresponding strategies for their stable performances were proposed. These provide guidance from the perspective of water pollution control for the sustainable development and benign circulation of the economy in Northeast China. [ABSTRACT FROM AUTHOR]

To investigate the mechanism of denitrifying phosphorus removal and provide functional strains for nitrogen and phosphorus removal, denitrifying phosphorus removal bacteria (DPB) were enriched and isolated from A2SBR. This study made use of controlling the inflow water operation mode of A2SBR for DPB enrichment and screening. The isolated DPB were complex formulated for construction of nitrogen and phosphorus removal functional bacteria. Two-stage inflow water operating mode and high inflow water rate enabled DPB to become rapidly dominant in the reactor. Five DPB strains were isolated and identified by the microbial identification system with fatty acids. The DPB strain and phosphorus accumulating organisms or denitrobacteria were complex formulated, the results showed that the best combination was b204 and 16. Its phosphorus removal rate was 85.78% and its denitrification efficiency was 75.02%, better than the single strains removal rate. Experimental results also showed that DPB could become dominant populations quickly with optimum cultivation conditions :rod appropriate influent. [ABSTRACT FROM AUTHOR]