Perennial grass-legume mixtures have been extensively used to restore degraded grasslands,increasing grassland productivity and forage quality.Tillage is crucial for seedbed preparation and sustainable weed management...Perennial grass-legume mixtures have been extensively used to restore degraded grasslands,increasing grassland productivity and forage quality.Tillage is crucial for seedbed preparation and sustainable weed management for the establishment of grass-legume mixtures.However,a common concern is that intensive tillage may alter soil characteristics,leading to losses in soil organic carbon(SOC).We investigated the plant community composition,SOC,soil microbial biomass carbon(MBC),soil enzyme activities,and soil properties in long-term perennial grass-legume mixtures under two different tillage intensities(once and twice)as well as in a fenced grassland(FG).The establishment of grass-legume mixtures increased plant species diversity and plant community coverage,compared with FG.Compared with once tilled grassland(OTG),twice tilled grassland(TTG)enhanced the coverage of high-quality leguminous forage species by 380.3%.Grass-legume mixtures with historical tillage decreased SOC and dissolved organic carbon(DOC)concentrations,whereas soil MBC concentrations in OTG and TTG increased by 16.0%and 16.4%,respectively,compared with FG.TTG significantly decreased the activity of N-acetyl-β-D-glucosaminidase(NAG)by 72.3%,whereas soil enzymeβ-glucosidase(βG)in OTG and TTG increased by 55.9%and 27.3%,respectively,compared with FG.Correlation analysis indicated a close association of the increase in MBC andβG activities with the rapid decline in SOC.This result suggested that MBC was a key driving factor in soil carbon storage dynamics,potentially accelerating soil carbon cycling and facilitating biogeochemical cycling.The establishment of grass-legume mixtures effectively improves forage quality and boosts plant diversity,thereby facilitating the restoration of degraded grasslands.Although tillage assists in establishing legume-grass mixtures by controlling weeds,it accelerates microbial activity and organic carbon decomposition.Our findings provide a foundation for understanding the process and effectiveness of restoration management in degraded grasslands.展开更多
为有效提高碳排放配额分配的合理性,并且避免年度结算时碳排放量超标导致环境污染加剧问题,提出基于奖惩因子的季节性碳交易机制,以园区综合能源系统(park integrated energy system,PIES)为对象进行低碳经济调度。首先,构建包含能量层...为有效提高碳排放配额分配的合理性,并且避免年度结算时碳排放量超标导致环境污染加剧问题,提出基于奖惩因子的季节性碳交易机制,以园区综合能源系统(park integrated energy system,PIES)为对象进行低碳经济调度。首先,构建包含能量层–碳流层–管理层的综合能源系统(integrated energy system,IES)运行框架,建立电气热多能流供需动态一致性模型;其次,分析系统内“日–季节–年度”碳排放特性,打破传统应用指标法的配额分配方法,采用灰色关联分析法建立碳排放配额分配模型,并基于奖惩阶梯碳价制定季节性碳交易机制;最后,以系统内全寿命周期运行成本及碳交易成本最小为目标,对执行季节性碳交易机制的PIES进行低碳经济调度,分析长时间尺度下季节性储能参与调度的减碳量。搭建IEEE 33节点电网5节点气网7节点热网的PIES,并基于多场景进行算例分析,验证此调度方法能够实现零碳经济运行,保证系统供能可靠性,为建立零碳园区奠定理论基础。展开更多
针对储能系统中电池组充放电过程中能量利用率以及系统运行安全性较低的问题,提出考虑SOC一致性的电池组双层动态均衡方法。首先,采用耦合电感与Flyback变换器搭建均衡系统双层架构,建立电池组端电压、均衡电流及占空比间的关联特性。...针对储能系统中电池组充放电过程中能量利用率以及系统运行安全性较低的问题,提出考虑SOC一致性的电池组双层动态均衡方法。首先,采用耦合电感与Flyback变换器搭建均衡系统双层架构,建立电池组端电压、均衡电流及占空比间的关联特性。为提高电池组的供能可靠性,系统引入故障切除功能,通过改变开关阵列导通状态实现故障电池组的快速切除;其次,考虑增补电池组剩余容量较大问题,利用传统最值法改进的双层极值法,以荷电状态(stage of charge,SOC)作为均衡目标变量,对增补电池组进行快速放电均衡;最后,设计充放电及静置均衡实验,对比传统最值法,分析常态及故障切除后电路的均衡速度与均衡效率。结果表明,提出的双层均衡方法可以将均衡速度提升约10%,且故障切除后电路的均衡效率最高可达95%以上。展开更多
A lead-free base glaze suitable for pearlescent pigments was prepared by a low-temperature solid-phase reaction with alkali waste.Tests were performed to evaluate the effects of the sintering conditions and alkali was...A lead-free base glaze suitable for pearlescent pigments was prepared by a low-temperature solid-phase reaction with alkali waste.Tests were performed to evaluate the effects of the sintering conditions and alkali waste composition on the prepared base glaze and pearlescent glaze.The experimental results show that partially replacing SiO_(2) with B_(2)O_(3) effectively reduced the sintering temperature and time to form a glass network,but the network structure becomes disconnected as the B_(2)O_(3) content increases.An amorphous base glaze was obtained when soda ash was replaced with a small amount of alkali waste,but increasing the addition of NaCl further was adverse to base glaze formation by resulting in crystallization of the base glaze and a decrease in the bridging oxygen content.The pearlescent pigment was thermally stable in the glaze at 750℃,while higher temperatures caused the crystalline phase of NaAlSiO_(4) to appear and adhere to the surface of pigment granules,which degraded the pearlescent effect of the glaze.展开更多
目的系统评价姜黄素对多囊卵巢综合征大鼠模型的疗效。方法检索中国知网、万方、维普、中国生物医学数据库、Web of Science、PubMed、Embase,检索时间为各数据库建立至2023年1月1日。采用Stata16.0进行Meta分析。结局指标包括性激素、...目的系统评价姜黄素对多囊卵巢综合征大鼠模型的疗效。方法检索中国知网、万方、维普、中国生物医学数据库、Web of Science、PubMed、Embase,检索时间为各数据库建立至2023年1月1日。采用Stata16.0进行Meta分析。结局指标包括性激素、血糖、炎症因子和磷脂酰肌醇3激酶(phosphatidylinositol-3-kinase,PI3K)/蛋白激酶B(protein kinase B,AKT)蛋白活性物表达水平。结果共纳入8篇随机对照动物实验,Meta分析结果表明,与对照组相比,姜黄素能够改善多囊卵巢综合征模型组的睾酮(SMD=-2.66,95%CI[-3.72,-1.61],P=0.000)、孕酮(SMD=2.82,95%CI[2.11,3.54],P=0.045)、促黄体生成素(SMD=-2.76,95%CI[-4.28,-1.23],P=0.000)、空腹血糖(SMD=-2.82,95%CI[-3.77,-1.86],P=0.000)、空腹胰岛素(SMD=-2.44,95%CI[-3.40,-1.49],P=0.000)、稳态模型胰岛素抵抗指数(SMD=-2.68,95%CI[-3.66,-1.69],P=0.000)、C反应蛋白(SMD=-1.96,95%CI[-2.71,-1.22],P=0.032)、白细胞介素6(SMD=-2.48,95%CI[-3.25,-1.72],P=0.047);而对雌二醇(SMD=-2.07,95%CI[-6.35,2.20],P=0.000)、促卵泡生成素(SMD=0.76,95%CI[-0.63,2.15],P=0.000)、肿瘤坏死因子-α(SMD=-1.64,95%CI[-6.02,2.73],P=0.000)、PI3K蛋白活性表达水平(SMD=-0.26,95%CI[-2.44,1.92],P=0.000)、AKT蛋白活性表达水平(SMD=-2.26,95%CI[-6.14,1.63],P=0.000)等指标的差异无统计学意义。结论姜黄素可作为支持性治疗手段治疗多囊卵巢综合征,通过降低血糖、缓解炎症、调节激素紊乱等多种机制发挥作用。展开更多
基金funded by the National Natural Science Foundation of China(32271776,32171616)the Special Sichuan Postdoctoral Research Projectsthe National Natural Science Foundation of Sichuan Province,China(2024NSFSC0309,2022NSFSC1769,2022NSFSC0110).
文摘Perennial grass-legume mixtures have been extensively used to restore degraded grasslands,increasing grassland productivity and forage quality.Tillage is crucial for seedbed preparation and sustainable weed management for the establishment of grass-legume mixtures.However,a common concern is that intensive tillage may alter soil characteristics,leading to losses in soil organic carbon(SOC).We investigated the plant community composition,SOC,soil microbial biomass carbon(MBC),soil enzyme activities,and soil properties in long-term perennial grass-legume mixtures under two different tillage intensities(once and twice)as well as in a fenced grassland(FG).The establishment of grass-legume mixtures increased plant species diversity and plant community coverage,compared with FG.Compared with once tilled grassland(OTG),twice tilled grassland(TTG)enhanced the coverage of high-quality leguminous forage species by 380.3%.Grass-legume mixtures with historical tillage decreased SOC and dissolved organic carbon(DOC)concentrations,whereas soil MBC concentrations in OTG and TTG increased by 16.0%and 16.4%,respectively,compared with FG.TTG significantly decreased the activity of N-acetyl-β-D-glucosaminidase(NAG)by 72.3%,whereas soil enzymeβ-glucosidase(βG)in OTG and TTG increased by 55.9%and 27.3%,respectively,compared with FG.Correlation analysis indicated a close association of the increase in MBC andβG activities with the rapid decline in SOC.This result suggested that MBC was a key driving factor in soil carbon storage dynamics,potentially accelerating soil carbon cycling and facilitating biogeochemical cycling.The establishment of grass-legume mixtures effectively improves forage quality and boosts plant diversity,thereby facilitating the restoration of degraded grasslands.Although tillage assists in establishing legume-grass mixtures by controlling weeds,it accelerates microbial activity and organic carbon decomposition.Our findings provide a foundation for understanding the process and effectiveness of restoration management in degraded grasslands.
文摘为有效提高碳排放配额分配的合理性,并且避免年度结算时碳排放量超标导致环境污染加剧问题,提出基于奖惩因子的季节性碳交易机制,以园区综合能源系统(park integrated energy system,PIES)为对象进行低碳经济调度。首先,构建包含能量层–碳流层–管理层的综合能源系统(integrated energy system,IES)运行框架,建立电气热多能流供需动态一致性模型;其次,分析系统内“日–季节–年度”碳排放特性,打破传统应用指标法的配额分配方法,采用灰色关联分析法建立碳排放配额分配模型,并基于奖惩阶梯碳价制定季节性碳交易机制;最后,以系统内全寿命周期运行成本及碳交易成本最小为目标,对执行季节性碳交易机制的PIES进行低碳经济调度,分析长时间尺度下季节性储能参与调度的减碳量。搭建IEEE 33节点电网5节点气网7节点热网的PIES,并基于多场景进行算例分析,验证此调度方法能够实现零碳经济运行,保证系统供能可靠性,为建立零碳园区奠定理论基础。
文摘针对储能系统中电池组充放电过程中能量利用率以及系统运行安全性较低的问题,提出考虑SOC一致性的电池组双层动态均衡方法。首先,采用耦合电感与Flyback变换器搭建均衡系统双层架构,建立电池组端电压、均衡电流及占空比间的关联特性。为提高电池组的供能可靠性,系统引入故障切除功能,通过改变开关阵列导通状态实现故障电池组的快速切除;其次,考虑增补电池组剩余容量较大问题,利用传统最值法改进的双层极值法,以荷电状态(stage of charge,SOC)作为均衡目标变量,对增补电池组进行快速放电均衡;最后,设计充放电及静置均衡实验,对比传统最值法,分析常态及故障切除后电路的均衡速度与均衡效率。结果表明,提出的双层均衡方法可以将均衡速度提升约10%,且故障切除后电路的均衡效率最高可达95%以上。
基金by the National Natural Science Foundation of China(No.51402097)the College Students Innovation and Entrepreneurship Training Program of Hubei University of Technology(No.202010500045)。
文摘A lead-free base glaze suitable for pearlescent pigments was prepared by a low-temperature solid-phase reaction with alkali waste.Tests were performed to evaluate the effects of the sintering conditions and alkali waste composition on the prepared base glaze and pearlescent glaze.The experimental results show that partially replacing SiO_(2) with B_(2)O_(3) effectively reduced the sintering temperature and time to form a glass network,but the network structure becomes disconnected as the B_(2)O_(3) content increases.An amorphous base glaze was obtained when soda ash was replaced with a small amount of alkali waste,but increasing the addition of NaCl further was adverse to base glaze formation by resulting in crystallization of the base glaze and a decrease in the bridging oxygen content.The pearlescent pigment was thermally stable in the glaze at 750℃,while higher temperatures caused the crystalline phase of NaAlSiO_(4) to appear and adhere to the surface of pigment granules,which degraded the pearlescent effect of the glaze.
文摘目的系统评价姜黄素对多囊卵巢综合征大鼠模型的疗效。方法检索中国知网、万方、维普、中国生物医学数据库、Web of Science、PubMed、Embase,检索时间为各数据库建立至2023年1月1日。采用Stata16.0进行Meta分析。结局指标包括性激素、血糖、炎症因子和磷脂酰肌醇3激酶(phosphatidylinositol-3-kinase,PI3K)/蛋白激酶B(protein kinase B,AKT)蛋白活性物表达水平。结果共纳入8篇随机对照动物实验,Meta分析结果表明,与对照组相比,姜黄素能够改善多囊卵巢综合征模型组的睾酮(SMD=-2.66,95%CI[-3.72,-1.61],P=0.000)、孕酮(SMD=2.82,95%CI[2.11,3.54],P=0.045)、促黄体生成素(SMD=-2.76,95%CI[-4.28,-1.23],P=0.000)、空腹血糖(SMD=-2.82,95%CI[-3.77,-1.86],P=0.000)、空腹胰岛素(SMD=-2.44,95%CI[-3.40,-1.49],P=0.000)、稳态模型胰岛素抵抗指数(SMD=-2.68,95%CI[-3.66,-1.69],P=0.000)、C反应蛋白(SMD=-1.96,95%CI[-2.71,-1.22],P=0.032)、白细胞介素6(SMD=-2.48,95%CI[-3.25,-1.72],P=0.047);而对雌二醇(SMD=-2.07,95%CI[-6.35,2.20],P=0.000)、促卵泡生成素(SMD=0.76,95%CI[-0.63,2.15],P=0.000)、肿瘤坏死因子-α(SMD=-1.64,95%CI[-6.02,2.73],P=0.000)、PI3K蛋白活性表达水平(SMD=-0.26,95%CI[-2.44,1.92],P=0.000)、AKT蛋白活性表达水平(SMD=-2.26,95%CI[-6.14,1.63],P=0.000)等指标的差异无统计学意义。结论姜黄素可作为支持性治疗手段治疗多囊卵巢综合征,通过降低血糖、缓解炎症、调节激素紊乱等多种机制发挥作用。
