化学添加剂对有氧胁迫下湿贮玉米发酵品质和有氧稳定性的影响

为研究苯甲酸钠、山梨酸钾和亚硝酸钠组成的化学添加剂对有氧胁迫处理的湿贮玉米发酵品质和有氧稳定性的影响。以35%和50%含水量的湿贮玉米为原料，设置对照组(无添加)、添加组1(2mL·kg^-1)、添加组2(4mL·kg^-1)在湿贮期设置不同时期有氧胁迫处理分别为:前期有氧胁迫处理(1~7d，Early air stress，EAS)、后期有氧胁迫处理(22~28 d，Later air stress，LAS)、全程有氧胁迫处理(1~28d，Full air stress，FAS)，28d后分析发酵品质、有氧稳定性以及有氧暴露7d后的发酵品质。结果表明：与对照组相比，添加组2的有机酸浓度最高，干物质损失最少，而且有氧稳定性最高。4mL·kg^-1的化学添加剂还显著抑制了酵母菌和大肠杆菌的生长。因此，化学添加剂明显消除了氧气的负面影响，并延长了有氧胁迫条件下的有氧稳定时间。     

基于物联网的空气源热泵式谷物干燥机试验研究

根据稻谷烘干的工艺要求，以泰州市某家庭农场的空气源热泵粮食烘干机为例，对基于物联网的空气源热泵热风机组在不同环境温度、匹配不同烘干机工况下的性能进行试验研究，通过采集干燥机热风温度、风量、耗电量等数据，计算热泵系统制热量、性能系数（coefficient of performance,COP）、除湿能耗比(specific moisture extraction rate,SMER)以及烘干成本等数据，对热泵系统的实际性能进行分析。结果表明：空气源热泵系统的性能受环境平均温度的显著影响，随环境温度升高，热泵的制热量逐步减少，COP逐渐增加、SMER增大；但当环境温度低于9℃时，热泵出风温度达不到设定值，COP和SMER均低于均值；当环境温度高于9℃时，系统表现出良好性能。     

番茄幼苗对高温时间段空气湿度控制的生理响应

为了解空气湿度对高温下番茄幼苗的生理影响，试验设计制作了智能控制自然光照生长箱，在夏季高温时段（10:00-16:00）设置了3种湿度处理，即空气相对湿度55%±5%（M处理）、70%±5%（H处理）和以不加湿作为对照（L处理）。结果表明，在平均温度为33 ℃的高温条件下，各处理番茄叶片中渗透调节物质（脯氨酸、可溶性糖、可溶性蛋白）的积累、POD活性都呈增加趋势，说明植株在不断的自我适应和调节；随处理时间延长，L处理和M处理的细胞膜相对透性增加，而H处理的细胞膜相对透性降低；而且处理期间，H处理的脯氨酸含量比L处理减少25%~70%，POD活性低14%~32%，说明植株在70%±5%的空气湿度下遭受的热胁迫较小,热害指数降低，耐热性提高。     

智能养猪工厂的研究进展与展望

工厂化养猪是畜牧业现代化的重要组成部分，是中国养猪业发展的必然趋势。中国养猪业面临着能繁母猪生产力水平低、健康管理水平低、智能设备利用率低、养殖成本高等产业突出问题。本文从猪群福利化健康养殖工艺、猪舍空气净化技术、猪只生长与健康状态感知技术、以及猪只精准饲喂和养殖机器人等智能作业装备4个方面，分析了智能养猪工厂建设中工艺、技术、装备的研究和发展现状，并对今后智能养猪工厂建设的重点方向进行了展望，以期为中国智能养猪工厂的创制提供参考。     

半履带式气垫车最佳载荷分配比的研究

对半履带式气垫车的动力学性能进行了分析，建立了载荷分配比的数学模型，探讨了驱动履带转率对最佳载荷分配比的影响。计算机仿真和试验结果表明，半履带式气垫车以最佳载荷分配比进行载荷匹配时，丰正常行驶的情况下，可使其总功率消耗相对最小。     

Effects of different vertical façade greenery systems on pedestrian thermal comfort in deep street canyons

Vertical greenery systems (VGSs) have been adopted in city planning operations to mitigate excess heat in hot and humid subtropical cities. This study focused on the influence of different arrangements of vertical greening on pedestrian thermal comfort and particulate matter with a diameter of 10 µm (PM₁₀) in street canyons. In this paper, the ENVI-met computational fluid dynamics (CFD) method was used to investigate the effects of different façade greenery arrangements with the same amount of greenery in the Nan Hai Yi Ku (NHYK) industrial district. On-site measurements were used to validate the simulation results in a transition season. The results showed that greening façades could improve pedestrians' thermal comfort with physiological equivalent temperature (PET) value reductions varying from 0.17 °C to 1.4 °C. Under a certain amount of greenery, the critical factor determining pedestrians' thermal comfort was the coverage rate of the greening façade near the pedestrian level. Specifically, increasing the greening façade coverage near the lower parts of street canyons could enhance the pedestrian-level cooling effect. In addition, the VGSs positively affected the pedestrian-level air quality in the street canyons. Nevertheless, the changes in pedestrian-level PM₁₀ concentration induced by the presence of VGSs were not very obvious under the building-parallel wind direction.     

Pollination of urban meadows – Plant reproductive success and urban-related factors influencing frequency of pollinators visits

Pollination is a key ecological service for human food security and the reproduction of the majority of flowering plants. This plant-animal interaction is crucial in both wild and urban habitats, however, increasing urbanization and change in land use alter these interactions. The concerns regarding pollination have led to numerous efforts aimed at improving the quality of wildlife in cities, however, understanding the importance of these activities warrants further research. In Warsaw, the Polish capital, we analyzed the influence of urban-related factors such as floral resource richness, the proportion of green areas in the proximity of foraging sites, air pollution or temperature on plant-pollinator interaction in 14 meadows. We also analyzed the reproductive success and the heterospecific pollen transfer in the case of plants growing in the meadows. Our study revealed that the frequency of visits to flowers was related to city-related factors, but the reaction varied among different groups of pollinators. For example, bumblebees were negatively influenced by higher air pollution, while the rest of the flower visitors were not, Syrphidae flies were more frequent flower visitors when the proportion of green area was higher in the buffer of 150 m, while we did not observe this tendency in other groups of flower visitors. Plants growing in Warsaw meadows were frequently visited and effectively pollinated - urban pollinator assemblages seem to provide sufficient pollination services to plants growing in the city. Species-rich communities were not a threat to pollination; we found mostly conspecific pollen grains on the stigmas of the studied plant species. The results of our study show that species-rich communities make a valuable contribution to pollinator conservation. The conservation activities, however, should be adjusted to the target group of pollinators, since different groups of flower visitors respond differently to urban-related factors studied.     

Associations between green space,air pollution and birthweight in Sydney Metropolitan Area,Australia

Growing number of evidence have reported that exposure to air pollution was associated with unfavourable birth outcomes while increased exposure to green spaces was associated with better birth outcomes. However, the effect of interactions between air pollution and green spaces on pregnancy outcomes remain unclear. Using the data on all the live births recorded in Sydney between 2016 January and 2017 December, we built up multilevel linear and logistic regression models with random intercepts for statistical area level 2 (SA2) to examine the association between residential levels of air pollution (NO2, PM2.5, SO2 and O3) and pregnancy outcomes including birthweight, low birthweight, and preterm birth. This was followed by assessment of potential effect modification by green space quantity by fitting 2-way interaction term between each air pollutants and green space quantity separately. Furthermore, building on the 2-way interaction term, we explored 3-way interactions by adding area level socio-economic status and population density. Higher levels of PM2.5, NO2 and SO2 were statistically significantly associated with decrease in birthweights (p < 0.05) in the adjusted models. We observed statistically significantly association between the lower risks of preterm birth and higher levels of NO2 in the adjusted models (p < 0.05). However, none of the other air pollutants were statistically significantly associated with the odds of low birthweight and preterm birth. In the adjusted models, green space quantity was statistically significantly associated with reduced odds of preterm birth (p < 0.05). The results for birthweights were in the same direction (p < 0.05) however, some of these associations did not remain statistically significant after adjusting the models for air pollution. In general, no associations were found for low birthweight. Statistically significant 2-way interactions between green space quantity and NO2, PM2.5 and SO2 levels indicated that association between moderate levels of NO2, PM2.5 and birthweight weakened in the greener areas (>20 %) especially in the affluent and densely populated areas while the effect of SO2 did not differ consistently across green space levels with benefit of exposure to the greenest areas (>40 %) was evident, yet not statistically significant. Our findings suggest that increasing green spaces in cities may help supporting a healthy start in life by decreasing harms of moderate levels of air pollution. Replication in different contexts and consideration of potentially contrasting results with different types of green space is warranted.     

Investigating non-destructive quantification and characterization of pomegranate fruit internal structure using X-ray computed tomography

In this study, X-ray computed tomography (CT) coupled with image analysis techniques was investigated for non-destructive characterization and quantification of internal structure of intact pomegranate fruit (cv. Shani-Yonay). X-ray tomograms of intact fruit were acquired using a V|Tome|X L240 commercial X-ray CT system based on X-ray radiation generated from a source voltage of 200 kV with the electron current set at 100 μA. Two-dimensional (2D) radioscopic images were acquired with a microfocus direct X-ray tube and used to reconstruct three-dimensional (3D) images to quantify volumes occupied by air space, albedo, and arils, using image processing software. The calculated volumes for these fruit fractions were 7.82 ± 1.09, 167.29 ± 16.54, and 182.11 ± 17.04 mL, estimated to contribute 2.22, 46.86 and 50.92% of total fruit volume, respectively. Destructive validation data were similar to non-destructive data, with volumes for albedo and arils of 166.08 ± 14.69 and 170.58 ± 14.25 mL, respectively, contributing 46.07 and 47.32% of total fruit volume. The remaining 6.61% of total fruit volume tested destructively could be due to the presence of air space and calyx. This work has demonstrated the capability of X-ray CT with image analysis as a useful non-destructive technique to study the quantity and distribution of edible and non-edible portions of pomegranate fruit.