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A counter-flow hollow fiber membrane-based evaporative cooler (HFMEC) was proposed. An experimental setup was developed to investigate the air handling performance of the HFMEC under various operating conditions. A numerical model was established and validated. The outlet air temperature predicted by the numerical model using free surface model showed a maximum deviation of 5% comparing with the experimental data. The model was further used to conduct a parametric analysis of the HFMEC. Six key parameters, including geometric specifications and operating conditions, were selected as factors for the sensitivity analysis. The cooling capacity and coefficient of performance (COP) were chosen as performance evaluation indicators. The simulation was performed with 27 cases for the orthogonal test. The range analysis revealed that the inlet air relative humidity and velocity, as well as packing fraction had significant impact on its cooling capacity and COP. Ranking the influence degree of key design parameters on performance evaluation indicators, this paper provides a convenient method to design and optimize the counter-flow HFMEC.

Building heat consumption is affected by factors such as building characteristics, surrounding non-heating users, and outdoor temperature. Therefore, in order to achieve precise and efficient heating, it is of great importance to study the effects of building characteristics and the existence of non-heating users on the building heat consumption. This paper proposed two factors to evaluate the influences of the building characteristics and the non-heating users on heat consumption in a multi-storey heating residential building. Based on the heat consumption without non-heating adjacent users, the top-side users, top-middle users, middle-side users, middle-middle users, bottom-side users and bottom-middle users are identified as six types of typical-location users. Taking the heat consumption of middle-middle users as the benchmark, location factors (LFs) are introduced to consider the influence of building characteristics on the heat consumption of different typical-location users. For each typical-location user, non-heating user factors (NHFs) are introduced to consider the influences of different distributed non-heating adjacent users on the heat consumption of each typical-location user. The results show that, for low-temperature hot water floor radiant heating system, the impact of upstairs adjacent non-heating users is greater than that of same-floor adjacent non-heating users, and the impact of downstairs adjacent non-heating users is minimal. Besides, it can be considered the non-heating user factors vary slightly with the outdoor temperature when the outdoor temperature is below 0 °C. The results provide a guide for heating operation regulation of residential buildings with non-heating users.

Geothermal has become a popular renewable energy in recent decades due to its properties of non-polluting, clean and large reserves. The vertical-butted geothermal well is a new structure for geothermal utilization. Two vertical boreholes with a certain distance are connected at bottoms by directional drilling to form a U-shape circulation loop. Due to the existence of the aquifers, the movement of underground water extends the heat exchange range and affects the geothermal system performance. This paper aims to develop an analytical method to solve the soil temperature field around the vertical-butted geothermal well with different flow directions. Taking the interacted effect of the two parallel pipes on the surrounding soil into consideration, the temperature distribution in the heat exchange zone is obtained. It is found that the temperature field changes significantly when the groundwater flow exists. The movement of underground water extends the downstream thermal radii from 4.8 m to 10.7 m, 10.6 m and 11.7 m when the flow directions are 0°, 45° and 90° toward the axis of the two pipes, respectively. The upstream thermal radii reduce from 5.4 m to 1.9 m for all the cases with groundwater movement. In addition, the effect of the underground water flow direction on the temperature field around the butted wells is analyzed. The results show that when the groundwater flow direction is perpendicular to the axis of the two pipes, the temperature field is the most beneficial to the performance of the vertical-butted geothermal well.

Geothermal resources are abundant in the Weihe Basin, which provides great potential for winter district heating in the Guanzhong area in western China. As a demonstration project for deep geothermal exploitation and utilization, four boreholes of over 2,000 m were drilled and paired to form two U-shaped downhole heat exchangers (DHEs) in the Xi’an Depression of the Weihe Basin. In this paper, the borehole equilibrium temperatures of these two DHEs, measured two years after the systems had been completed, are presented. The analysis of the borehole temperatures show that: (1) the thermal and hydrological regimes of the study area are stable, as indicated by the highly consistent borehole temperatures among the four boreholes, both horizontally and vertically. (2) the geothermal gradient range down to the depth of 2,000 m in this area is 3.45 ˜ 3.47°C/hm with an average of 3.46 ± 0.01°C/hm, substantially higher than the regional mean and implying a great geothermal energy exploitation potential; the high geothermal gradient anomaly can be attributed to the rather thin crust in the Weihe Basin with a relatively high mantle heat flow and hydrothermal convection systems involving fluid circulation in nearby discordogenic fault zones. (3) the Lantian-Bahe Formation has the features of stable distribution, good aquifer yield, high transmissivity, high permeability and high thermal conductivity, and hence, it is a good hosting stratum to the horizontal section of U-shaped DHEs in this area to maximize heat exchange efficiency and sustainability.

In this study, algae and microcystins (MC-LR and MC-RR) were studied in 6 reservoirs in the northeastern part of Haihe River Basin. The results indicate that the eutrophication degree of most reservoirs has been obviously improved, but Yuqiao reservoir and Yanghe reservoir are still in the state of eutrophication. The MC-LR and MC-RR were also detected in Yuqiao reservoir and Yanghe reservoir. In addition, cyanobacteria were dominant spices in the eutrophic reservoirs, and the concentration of microcystins was positively correlated with algae density. Although the concentration of MC-LR is lower than the concentration limits of sanitary standard for drinking water. It is suggested that it should be monitored during the outbreak of cyanobacteria, especially in the later stage of outbreak considering a risk for the health of the water supply population.

Four compounds were identified from female sex-pheromone gland extracts of Acleris fimbriana Merick, an important pest in northern fruit orchards of China, by gas chromatography, gas chromatography – mass spectrometry, and flight-tunnel and field-trapping tests. These compounds were (E)-11,13-tetradecadienal (E11,13-14:Ald), (E)-11,13-tetradecadien-1-ol (E11,13-14:OH), (E)-11-tetradecenyl acetate (E11-14:Ac), and (E)-11,13-tetradecadienyl acetate (E11,13-14:Ac). In field-trapping tests, traps baited with E11,13-14:Ald alone produced the highest trap captures of male A. fimbriana, but the other three individual compounds did not capture any mates. Addition of E11,13-14:Ac to E11,13-14:Ald enhanced trap capture, whereas addition of E11-14:Ac had no effect. A ternary blend of E11,13-14:Ald, E11,13-14:Ac, and E11-l4:Ac in a 6:4:1 ratio captured 7.5 times mean males per trap than virgin females. E11,13-14:OH inhibited trap capture when it was added to E11,13-14:Ald or the ternary blend. This pheromone could be used to monitor populations of A. fimbriana and to control this important pest of fruits in China.

This paper combined the advantages of each maximum power point tracking (MPPT) algorithm, put forward a kind of algorithm with higher speed and higher precision, based on this algorithm designed a maximum power point tracking controller with ARM. The controller, communication technology and PC software formed a control system. Results of the simulation and experiment showed that the process of maximum power tracking was effective, and the system was stable.

The MPPT controller was a hardware device for tracking the maximum power point of solar photovoltaic array. Multiple controllers could be working as networking mode by specific communicating protocol. In this article, based on C++ GUI programming with Qt frame, we designed one sort of desktop application for monitoring and analyzing operational parameter of MPPT controller. The type of communicating protocol for building network was Modbus protocol which using Remote Terminal Unit mode and The desktop application of host computer was connected with all the controllers in the network through RS485 communication or ZigBee wireless communication. Using this application, user could monitor the parameter of controller wherever they were by internet.

The temporal and spatial distribution of PAHs in surface-water from the typical rivers of North China was investigated. PAHs in typical rivers ranged from n.d. to 1.98 ng/L. LMW PAHs (2 and 3-ring) were abundant in surface water with high detection frequencies in Beisanhe River, while HMW PAHs (4 and 6-ring) were abundant in Luanhe River. Specific PAHs with its ratios were measured in order to deduce the possible sources of PAHs contaminant. The results indicate that the PAHs were from combustion processes in Beisanhe River, while PAHs were from petroleum products in Luanhe River.

Aim: To find a quick and reliable diagnostic technique for penicillin nonsusceptible Streptococcus pneumoniae (PNSSP) from Nanjing, China. Methods and Results: A total of 130 S. pneumoniae clinical isolates and 50 healthy carriers’ isolates were collected from seven teaching hospitals in Nanjing between March 2005 and June 2007. Three different methods, PCR, seminested-PCR, and PCR-RFLP, were applied in detecting PNSSP. The prevalence of PNSSP was 73·9%, the penicillin-resistance rate of children’s group and adults’ group were 87·8% and 31·2%, respectively. The PCR method had difficulty in identifying intermediate-resistant and resistant isolates, the PCR-RFLP method could only be used for susceptible isolates and had poor sensitivity. Seminested-PCR was fast, sensitive for detection, and successfully differentiated between moderately and highly resistant S. pnemoniae; 96·1% of the PCR results were in agreement with the minimum inhibitory concentration (MIC) data. Conclusions: The penicillin resistance rate in isolates from children was much higher than of isolates from adults in China. Seminested-PCR for pbp1A was the best diagnostic method. Significance and Impact of the Study: We compared three different strategies for the first time in identification of PNSSP in China. In conclusion, seminested-PCR can be applied in clinical microbiology laboratories for detection of serious infections caused by S. pneumoniae.

The goal of this study was to clarify the relationship between blood pressure and inducible nitric oxide synthase (iNOS) activity. Different levels of blood pressure were obtained by long-term (six days) intravenous infusion of different concentrations (0.3%-8%) of NaCl solution to normal SD rats. iNOS activity assay and measurement of urinary nitrate/nitrite (UNOx), an index of NO production of the whole body, were carried out by isotope-labeled L-arginine conversion rate measurement and Greiss Reaction respectively. Groups of normotensive and hypertensive rats including normal Wistar rats, normal Sprague-Dawley (SD) rats, high NaCl-induced hypertensive rats (NaHR) and spontaneously hypertensive rats (SHR) were used to detect the changes in iNOS protein under normotension and hypertension by Western blotting. iNOS activity of aorta and kidney tissues and UNOx increased more significantly in hypertensive animals than in the normotensive control ones. Accordingly, iNOS protein in the aortas of NaHR and SHR increased by 149% and 261% respectively. It is suggested that in addition to cytokine and bacterial products etc, blood pressure is also an effective regulatory factor involved in iNOS activation and expression.

Angiographic findings in seventy cases of maxillofacial hemangioma are reported. The tumors have been divided into four types: (1) plexiform hemangioma, (2) cavernous hemangioma with venous drainage, (3) cavernous hemangioma without venous drainage, and (4) the so-called "diffuse type" of cavernous hemangioma. The angiographic features of the four types are described, and clinical application is evaluated. The angiograms demonstrate the location, extent, blood supply, and drainage of the tumors and show whether they communicate intracranially, thus providing valuable criteria for planning and determining the mode of treatment.