采用密闭式静态箱-气相色谱法和通气法研究了盆栽试验条件下包膜/抑制剂结合型肥料对土壤N_2O排放和氨挥发的影响。结果表明:与普通尿素(U)相比,包膜/抑制剂结合型尿素(T2~T4)延迟了土壤N_2O排放和氨挥发出现峰值的时间。包膜尿素(T1)...采用密闭式静态箱-气相色谱法和通气法研究了盆栽试验条件下包膜/抑制剂结合型肥料对土壤N_2O排放和氨挥发的影响。结果表明:与普通尿素(U)相比,包膜/抑制剂结合型尿素(T2~T4)延迟了土壤N_2O排放和氨挥发出现峰值的时间。包膜尿素(T1)、含有抑制剂的包膜尿素(T2)、抑制剂涂层尿素后包膜(T3)、包膜尿素与抑制剂混合(T4)处理N_2O累积排放量比U处理显著减少了27%、39%、49%、39%(P<0.05),T3处理N_2O累积排放量最小,为0.87 kg N·hm-2,显著低于其他处理(P<0.05),T2和T4处理之间差异不显著(P>0.05);包膜/抑制剂型肥料能够减少土壤氨挥发,T3处理氨挥发量最小,为13.68 kg N·hm-2,与U处理相比,T2、T3和T4处理氨挥发量分别显著减少了34%、45%和31%(P<0.05);T2和T3处理玉米产量分别比U处理显著提高13.03%和17.98%(P<0.05);T3处理氮素利用率最高,为58.22%;成本效益分析结果表明,T3与其他处理相比经济净效益最大,为3 061.6元·hm-2。综上,包膜/抑制剂结合型尿素可以减少土壤N_2O排放和氨挥发的气态损失,提高产量和氮素利用率,其中抑制剂涂层尿素后包膜(T3)处理效果最佳。展开更多
We propose a system for remote measurement of low-energy radiation, which is implemented using an ARM board and a Zig Bee module. The ARM STM32 F103 board employs a horizontal and vertical moving CMOS camera for front...We propose a system for remote measurement of low-energy radiation, which is implemented using an ARM board and a Zig Bee module. The ARM STM32 F103 board employs a horizontal and vertical moving CMOS camera for front-end data acquisition. The camera can detect radiation over different coordinates given by latitude and longitude in a determined area. For image processing, we used the subtraction–summation algorithm based on gradient multiplication and edge detection. Compared to algorithms such as the max grayscale value, subtraction–summation, and whole summation, the improved subtraction–summation algorithm filters noise and removes the background grayscale value of the whole image to attain higher accuracy, stronger anti-interference ability, and better consistency to determine the radiation dose. We dedicated one port of the transmission module to send data through the STM32 F103 board, whereas another port is connected to the Zig Bee module for data reception. By employing this architecture, we achieved low power consumption and fast response in the remote data transmission.Overall, the proposed system performs the remote measurement of low-energy radiation with stability andreliability, which is required for critical scenarios such as the remote detection of nuclear radiation.展开更多
Background Miniature pig （minipig） is increasingly used as a large animal model for a variety of biomedical studies. Little information is available in the literature on anatomy, histology and sialogragh of the subm...Background Miniature pig （minipig） is increasingly used as a large animal model for a variety of biomedical studies. Little information is available in the literature on anatomy, histology and sialogragh of the submandibular gland of the minipig. The purpose of this study was to characterize the morphology of a miniature pig＇s （minipig） submandibular gland as a large animal model for further biomedical studies. Methods Five minipigs were subjected to sialographic, anatomic, histologic, histochemical and uhrastructural evaluations for submandibular glands. Results Sialograms showed a long, horizontal main excretory duct and a pear-shaped gland located inferoposterior to the angle of the mandible. The submandibular glands lied superficial to the suprahyoid, and infrahyoid muscle groups, and were covered by the inferior portion of the parotid gland. The submandibular glands were characterized by a mixed parenchyma of mucous and serous secretory aeini. Alcian blue （AB） staining and periodic acid-Schiff （PAS） reactions demon-strated that minipig submandibular glands synthesized and secreted acid mucous substances by serous cells and polysaccharide, and neutral mucous substances, by mucous cells. Conclusion The submandibular gland of the minipig is considered a useful large salivary gland animal model for biomedical studies.展开更多
文摘采用密闭式静态箱-气相色谱法和通气法研究了盆栽试验条件下包膜/抑制剂结合型肥料对土壤N_2O排放和氨挥发的影响。结果表明:与普通尿素(U)相比,包膜/抑制剂结合型尿素(T2~T4)延迟了土壤N_2O排放和氨挥发出现峰值的时间。包膜尿素(T1)、含有抑制剂的包膜尿素(T2)、抑制剂涂层尿素后包膜(T3)、包膜尿素与抑制剂混合(T4)处理N_2O累积排放量比U处理显著减少了27%、39%、49%、39%(P<0.05),T3处理N_2O累积排放量最小,为0.87 kg N·hm-2,显著低于其他处理(P<0.05),T2和T4处理之间差异不显著(P>0.05);包膜/抑制剂型肥料能够减少土壤氨挥发,T3处理氨挥发量最小,为13.68 kg N·hm-2,与U处理相比,T2、T3和T4处理氨挥发量分别显著减少了34%、45%和31%(P<0.05);T2和T3处理玉米产量分别比U处理显著提高13.03%和17.98%(P<0.05);T3处理氮素利用率最高,为58.22%;成本效益分析结果表明,T3与其他处理相比经济净效益最大,为3 061.6元·hm-2。综上,包膜/抑制剂结合型尿素可以减少土壤N_2O排放和氨挥发的气态损失,提高产量和氮素利用率,其中抑制剂涂层尿素后包膜(T3)处理效果最佳。
基金supported by the Plan for Scientific Innovation Talent of Henan Province(No.154100510007)the Program for Creative Export Mental Project of National Undergraduate Students(No.CEPNU 5101022000004)
文摘We propose a system for remote measurement of low-energy radiation, which is implemented using an ARM board and a Zig Bee module. The ARM STM32 F103 board employs a horizontal and vertical moving CMOS camera for front-end data acquisition. The camera can detect radiation over different coordinates given by latitude and longitude in a determined area. For image processing, we used the subtraction–summation algorithm based on gradient multiplication and edge detection. Compared to algorithms such as the max grayscale value, subtraction–summation, and whole summation, the improved subtraction–summation algorithm filters noise and removes the background grayscale value of the whole image to attain higher accuracy, stronger anti-interference ability, and better consistency to determine the radiation dose. We dedicated one port of the transmission module to send data through the STM32 F103 board, whereas another port is connected to the Zig Bee module for data reception. By employing this architecture, we achieved low power consumption and fast response in the remote data transmission.Overall, the proposed system performs the remote measurement of low-energy radiation with stability andreliability, which is required for critical scenarios such as the remote detection of nuclear radiation.
文摘Background Miniature pig （minipig） is increasingly used as a large animal model for a variety of biomedical studies. Little information is available in the literature on anatomy, histology and sialogragh of the submandibular gland of the minipig. The purpose of this study was to characterize the morphology of a miniature pig＇s （minipig） submandibular gland as a large animal model for further biomedical studies. Methods Five minipigs were subjected to sialographic, anatomic, histologic, histochemical and uhrastructural evaluations for submandibular glands. Results Sialograms showed a long, horizontal main excretory duct and a pear-shaped gland located inferoposterior to the angle of the mandible. The submandibular glands lied superficial to the suprahyoid, and infrahyoid muscle groups, and were covered by the inferior portion of the parotid gland. The submandibular glands were characterized by a mixed parenchyma of mucous and serous secretory aeini. Alcian blue （AB） staining and periodic acid-Schiff （PAS） reactions demon-strated that minipig submandibular glands synthesized and secreted acid mucous substances by serous cells and polysaccharide, and neutral mucous substances, by mucous cells. Conclusion The submandibular gland of the minipig is considered a useful large salivary gland animal model for biomedical studies.
