Composting as a solution to the increasing generation of municipal solid waste (MSW), also contribute to GHGs emission when not controlled and could lack some basic nutrients, especially nitrogen. This study assessed ...Composting as a solution to the increasing generation of municipal solid waste (MSW), also contribute to GHGs emission when not controlled and could lack some basic nutrients, especially nitrogen. This study assessed the split-additions of nitrogen-rich substrate to composting materials and their effect on GHGs emissions as well as the quality of the composts. Nitrogen-rich substrates formulated from pig and goat manure were co-composted with MSW for a 12-weeks period by split adding at mesophilic (˚C) and thermophilic (>50˚C) stages in five different treatments. Representative samples from the compost were taken from each treatment for physicochemical, heavy metals and bacteriological analysis. In-situ CH<sub>4</sub>, CO<sub>2</sub>, N<sub>2</sub>O gas emissions were also analyzed weekly during composting. It was observed that all the treatments showed significant organic matter decomposition, reaching thermophilic temperatures in the first week of composting. The absence affects the suitable agronomic properties. All nitrogen-rich substrate applied at thermophilic stage (Treatment two) recorded the highest N, P and K concentrations of 1.34%, 0.97% and 2.45%, respectively with highest nitrogen retention. In terms of GHG emissions, CO<sub>2</sub> was highest at the thermophilic stage when N-rich substrate was added in all treatment, while CH<sub>4</sub> was highest in the mesophilic stage with N-rich substrate addition. N<sub>2</sub>O showed no specific trend in the treatments. Split addition of the N-rich substrate for co-composting of MSW produced compost which is stable, has less nutrient loss and low GHG emissions. Split addition of a nitrogen-rich substrate could be an option for increasing the fertilizer value of MSW compost.展开更多
3,4-Dinitrofurazanfuroxan(DNTF),as a high-energy-density material,features good thermal stability and wide applications.This study aimed to elucidate the thermal decomposition mechanism of DNTF combined with nitrogen-...3,4-Dinitrofurazanfuroxan(DNTF),as a high-energy-density material,features good thermal stability and wide applications.This study aimed to elucidate the thermal decomposition mechanism of DNTF combined with nitrogen-rich compounds containing N-H.The thermal stabilities of DNTF and its hybrid systems were investigated using differential thermal analysis/thermogravimetry(TG),vacuum stability test,and accelerating rate calorimetry under isothermal,non-isothermal,and adiabatic conditions,respectively.Results showed that the thermal stability and thermal safety of DNTF significantly decreased after combining with nitrogen-rich compounds containing N-H.Calculation results showed that the activation energy of the DNTF hybrid systems was significantly lower than that of DNTF.The TGIR was used to monitor the generation of fugitive gases during the thermal decomposition of the DNTF/5-aminotetrazole(5-ATZ)hybrid.Moreover,the nitrogen-rich molecules containing N-H interacted extensively with DNTF,and this interaction accelerated the thermal degradation of DNTF.展开更多
Ma's CuI/proline procedure for the catalytic cross coupling between nitrogen heterocycles and aryl halides was markedly improved. The key finding was that K3PO4 was a much better base than K2CO3 for the reaction. Wit...Ma's CuI/proline procedure for the catalytic cross coupling between nitrogen heterocycles and aryl halides was markedly improved. The key finding was that K3PO4 was a much better base than K2CO3 for the reaction. With this new reaction condition the cross coupling with aryl iodides could be accomplished in 1,4-dioxane instead of DMSO. This reactin also could be carried out in DMF. Furthermore, the coupling yields under the new conditions are usually higher than in Ma's original methods.展开更多
After the preparation of 1,4-bis(4,5-dihydro-lH-imidazol-2-yl)benzene(bdib), a nitrogen heterocycle with potential coordination manners of both cis- and trans-configuration forms, three complexes, including cis-[...After the preparation of 1,4-bis(4,5-dihydro-lH-imidazol-2-yl)benzene(bdib), a nitrogen heterocycle with potential coordination manners of both cis- and trans-configuration forms, three complexes, including cis-[Cuz(bdib )2(/L-OCH3)2]Cl2·2MeOH(1), trans-[Cu(bdib)(AcO)2]n(2), and cis-[Ag2(bdib)2](NO3)2.2H20(3), were successfully self-assembled. Complexes 1 and 2 crystallized in the monoclinic system with P21/n space group and complex 3 in the triclinic system with P1 space group.展开更多
The synthesis, preparation, chemical reactivities and biological activity of simple heterocyclic and heteropolycyclic nitrogen systems as small units as functional pyrazoles, pyridine and pyrimidine, and the related f...The synthesis, preparation, chemical reactivities and biological activity of simple heterocyclic and heteropolycyclic nitrogen systems as small units as functional pyrazoles, pyridine and pyrimidine, and the related fused systems are reviewed. Among the various possible routes to the formation, isomeric structures have been cited because of patented reaching advanced phases of clinical trials, from 2000 to 2020.展开更多
The nitrogen content of tetrazolo triazines is 68.9%.In this paper,tetrazolotriazines was synthetized.The TG-DSC test indicated its decomposition process in detail.The non-isothermal kinetic parameters were speculated...The nitrogen content of tetrazolo triazines is 68.9%.In this paper,tetrazolotriazines was synthetized.The TG-DSC test indicated its decomposition process in detail.The non-isothermal kinetic parameters were speculated by Kissinger and Ozawa methods.It revealed the mechanism function of thermal decomposition.The impact and friction sensitivity were tested.The detonation pressure and velocity were calculated.It has a wide range of potential applications as a kind of energetic material.展开更多
研究提出一种通过化学键键能差进行能量密度快速估算的方法,和一种利用拉普拉斯键级和分子片段键离解能相结合快速判断笼型结构稳定性的方法。通过穷举法构建了基于Noradamantane的所有富氮骨架及其435种硝基衍生物,应用上述计算方法筛...研究提出一种通过化学键键能差进行能量密度快速估算的方法,和一种利用拉普拉斯键级和分子片段键离解能相结合快速判断笼型结构稳定性的方法。通过穷举法构建了基于Noradamantane的所有富氮骨架及其435种硝基衍生物,应用上述计算方法筛选兼具高能量密度和稳定性的分子结构,并采用量子化学能量计算和过渡态反应势垒计算验证筛选结果的可靠性。计算发现了两种兼顾高能量密度和结构稳定性的硝基化合物,其爆热、爆速、爆压和金属加速能力的理论计算最大值分别达到7.77 k J·g^(-1)、10.1 km·s^(-1)、47 GPa和1.14倍HMX的金属加速能力,且结构分解反应势垒≥96 k J·mol^(-1)。本研究所建立的含能分子能量密度和稳定性快速筛选方法,可为高能稳定的含能分子设计提供参考。展开更多
文摘Composting as a solution to the increasing generation of municipal solid waste (MSW), also contribute to GHGs emission when not controlled and could lack some basic nutrients, especially nitrogen. This study assessed the split-additions of nitrogen-rich substrate to composting materials and their effect on GHGs emissions as well as the quality of the composts. Nitrogen-rich substrates formulated from pig and goat manure were co-composted with MSW for a 12-weeks period by split adding at mesophilic (˚C) and thermophilic (>50˚C) stages in five different treatments. Representative samples from the compost were taken from each treatment for physicochemical, heavy metals and bacteriological analysis. In-situ CH<sub>4</sub>, CO<sub>2</sub>, N<sub>2</sub>O gas emissions were also analyzed weekly during composting. It was observed that all the treatments showed significant organic matter decomposition, reaching thermophilic temperatures in the first week of composting. The absence affects the suitable agronomic properties. All nitrogen-rich substrate applied at thermophilic stage (Treatment two) recorded the highest N, P and K concentrations of 1.34%, 0.97% and 2.45%, respectively with highest nitrogen retention. In terms of GHG emissions, CO<sub>2</sub> was highest at the thermophilic stage when N-rich substrate was added in all treatment, while CH<sub>4</sub> was highest in the mesophilic stage with N-rich substrate addition. N<sub>2</sub>O showed no specific trend in the treatments. Split addition of the N-rich substrate for co-composting of MSW produced compost which is stable, has less nutrient loss and low GHG emissions. Split addition of a nitrogen-rich substrate could be an option for increasing the fertilizer value of MSW compost.
基金the financially sponsor of the Natural Science Foundation of China(Grant No.51972278)the Outstanding Youth Science and Technology Talents Program of Sichuan(Grant No.19JCQN0085)the Open Project of State Key Laboratory of Environment-friendly Energy Materials(Southwest University of Science and Technology,Grant No.21fksy19)。
文摘3,4-Dinitrofurazanfuroxan(DNTF),as a high-energy-density material,features good thermal stability and wide applications.This study aimed to elucidate the thermal decomposition mechanism of DNTF combined with nitrogen-rich compounds containing N-H.The thermal stabilities of DNTF and its hybrid systems were investigated using differential thermal analysis/thermogravimetry(TG),vacuum stability test,and accelerating rate calorimetry under isothermal,non-isothermal,and adiabatic conditions,respectively.Results showed that the thermal stability and thermal safety of DNTF significantly decreased after combining with nitrogen-rich compounds containing N-H.Calculation results showed that the activation energy of the DNTF hybrid systems was significantly lower than that of DNTF.The TGIR was used to monitor the generation of fugitive gases during the thermal decomposition of the DNTF/5-aminotetrazole(5-ATZ)hybrid.Moreover,the nitrogen-rich molecules containing N-H interacted extensively with DNTF,and this interaction accelerated the thermal degradation of DNTF.
文摘Ma's CuI/proline procedure for the catalytic cross coupling between nitrogen heterocycles and aryl halides was markedly improved. The key finding was that K3PO4 was a much better base than K2CO3 for the reaction. With this new reaction condition the cross coupling with aryl iodides could be accomplished in 1,4-dioxane instead of DMSO. This reactin also could be carried out in DMF. Furthermore, the coupling yields under the new conditions are usually higher than in Ma's original methods.
基金Supported by the National Natural Science Foundation of China(No.20771073)
文摘After the preparation of 1,4-bis(4,5-dihydro-lH-imidazol-2-yl)benzene(bdib), a nitrogen heterocycle with potential coordination manners of both cis- and trans-configuration forms, three complexes, including cis-[Cuz(bdib )2(/L-OCH3)2]Cl2·2MeOH(1), trans-[Cu(bdib)(AcO)2]n(2), and cis-[Ag2(bdib)2](NO3)2.2H20(3), were successfully self-assembled. Complexes 1 and 2 crystallized in the monoclinic system with P21/n space group and complex 3 in the triclinic system with P1 space group.
文摘The synthesis, preparation, chemical reactivities and biological activity of simple heterocyclic and heteropolycyclic nitrogen systems as small units as functional pyrazoles, pyridine and pyrimidine, and the related fused systems are reviewed. Among the various possible routes to the formation, isomeric structures have been cited because of patented reaching advanced phases of clinical trials, from 2000 to 2020.
基金Supported by the State Key Laboratory of Explosion Science and Technology(Beijing Institute of Technology)(YBKT16-09,QNKT16-03)
文摘The nitrogen content of tetrazolo triazines is 68.9%.In this paper,tetrazolotriazines was synthetized.The TG-DSC test indicated its decomposition process in detail.The non-isothermal kinetic parameters were speculated by Kissinger and Ozawa methods.It revealed the mechanism function of thermal decomposition.The impact and friction sensitivity were tested.The detonation pressure and velocity were calculated.It has a wide range of potential applications as a kind of energetic material.
文摘研究提出一种通过化学键键能差进行能量密度快速估算的方法,和一种利用拉普拉斯键级和分子片段键离解能相结合快速判断笼型结构稳定性的方法。通过穷举法构建了基于Noradamantane的所有富氮骨架及其435种硝基衍生物,应用上述计算方法筛选兼具高能量密度和稳定性的分子结构,并采用量子化学能量计算和过渡态反应势垒计算验证筛选结果的可靠性。计算发现了两种兼顾高能量密度和结构稳定性的硝基化合物,其爆热、爆速、爆压和金属加速能力的理论计算最大值分别达到7.77 k J·g^(-1)、10.1 km·s^(-1)、47 GPa和1.14倍HMX的金属加速能力,且结构分解反应势垒≥96 k J·mol^(-1)。本研究所建立的含能分子能量密度和稳定性快速筛选方法,可为高能稳定的含能分子设计提供参考。