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Electrosynthesis of hydroxylamine from nitrate reduction in water

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Science China Chemistry 2023年第6期66卷 1758-1762页

作者： Xianen Lan Chuanqi Cheng Chengying Guo Minghao Guo tieliang li Yongmeng Wu Yifu Yu Bin Zhang Institute of Molecular Plus Department of ChemistrySchool of ScienceTianjin UniversityTianjin 300072China Institute of New Energy Materials School of Materials Science and EngineeringTianjin UniversityTianjin 300072China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China

Hydroxylamine(NH_(2)OH),a vital but unstable industrial feedstock,is presently prepared under harsh conditions that cause environmental and energy concerns.Here,we report an electrochemical method to prepare oximes,which serve as precursors for NH_(2)OH after facile hydrolysis.The carbon-supported amorphous Mn electrocatalyst delivers a current density of~100 mA cm^(-2) with a Faradaic efficiency of 40.92%and a yield rate of 0.251 mmol cm^(-2)h^(-1) for formaldoxime(CH_(2)NOH)generation by using nitrate and formaldehyde as reactants.Formaldoxime can be easily released to produce NH_(2)OH via hydrolysis.Impressively,this method exhibits an economic advantage over conventional manufacturing based on techno-economic analysis.A series of control experiments,in situ characterizations,and theoretical simulations unveil the reaction mechanism via the spontaneous reaction between an aldehyde and*NH_(2)OH intermediate derived from nitrate electroreduction.The high activity of Mn originates from its inhibitory effects on the further reduction of key*NH_(2)OH intermediate.This strategy opens a sustainable and green way for NH_(2)OH synthesis under mild conditions using renewable energy.

关键词： electrosynthesis hydroxylamine nitrate reduction amorphous Mn reaction pathway

Electrosynthesis ofN-labeled amino acids fromN-nitrite and ketonic acids

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Science China Chemistry 2023年

作者： Yongmeng Wu Mengyang li tieliang li Jinghui Zhao Ziyang Song Bin Zhang Department of Chemistry School of Science Institute of Molecular Plus Tianjin University Tianjin Key Laboratory of Molecular Optoelectronic Science Key Laboratory of Systems Bioengineering (Ministry of Education) Tianjin University

15N isotope-labeled amino acids(15N-amino acids) are crucial in the fields of biology, medicine, and chemistry.15N-amino acids are conventionally synthesized through microbial fermentation and chemical reductive amination of ketonic acids methodologies, which usually require complicated procedures, high temperatures, or toxic cyanide usage, causing energy and environmental concerns. Here, we report a sustainable pathway to synthesize15N-amino acids from readily available15N-nitrite(15NO2-)and biomass-derived ketonic acids under ambient conditions driven by renewable electricity. A mechanistic study demonstrates a15N-nitrite→15NH2OH→15N-pyruvate oxime→15N-alanine reaction pathway for15N-alanine synthesis. Moreover, this electrochemical strategy can synthesize six15N-amino acids with 68%–95% yields. Furthermore, a15N-labeled drug of15N-tiopronin,the most commonly used hepatitis treatment drug, is fabricated using15N-glycine as the building block. Impressively,15N sources can be recycled by the electrooxidation of15NH4+to15NO2-with a method economy. This work opens a venue for the green synthesis of15N-labeled compounds or drugs.

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基于二次分解因果分析和深度学习的短期风电功率预测

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河北电力技术 2024年第1期43卷 77-83页

作者：梅晓辉李国翊李铁良关猛国网河北省电力有限公司衡水供电分公司河北衡水053000 北京派克盛宏电子科技有限公司北京100071

为实现精准的风电功率预测,提出了一种基于二次分解因果分析和深度学习的风电功率预测模型。首先,通过完备集成经验模态分解算法对风电功率和风速序列进行一次分解,并采用经验小波变换算法对风电功率和风速序列的高频分量进行二次分解,... 详细信息

为实现精准的风电功率预测,提出了一种基于二次分解因果分析和深度学习的风电功率预测模型。首先,通过完备集成经验模态分解算法对风电功率和风速序列进行一次分解,并采用经验小波变换算法对风电功率和风速序列的高频分量进行二次分解,以降低原始序列的复杂程度。其次,通过Granger因果关系检验方法对各风速分量与风电功率分量进行因果分析,以此实现风电功率各分量的输入变量选择。最后,利用耦合注意力机制的双向门控循环单元对风电功率分量进行预测,并集成得到最终的风电功率预测结果。通过风电厂实际运行数据进行试验,并与多个典型模型进行比较,结果表明所提模型具有较高的预测精度,其决定系数达到了0.98,能够实现较精准的风电功率预测。

关键词：风电功率二次分解 Granger因果关系检验双向门控循环单元注意力机制

极化码的分布式CRC辅助低复杂度逐次抵消翻转译码

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移动信息 2024年第3期46卷 276-279页

作者：李炳槐郭铁梁王奎奎梧州学院电子与信息工程学院广西梧州543002

为提高极化码的译码效率,文中提出了一种新颖的逐次抵消翻转(SCF)译码。与传统的SCF译码相比,其可以使用分布式CRC比特来降低计算复杂度。该译码通过提前终止对第一次SC译码的失败帧的译码,来减少信息比特的估计数量,同时尝试最小化附... 详细信息

为提高极化码的译码效率,文中提出了一种新颖的逐次抵消翻转(SCF)译码。与传统的SCF译码相比,其可以使用分布式CRC比特来降低计算复杂度。该译码通过提前终止对第一次SC译码的失败帧的译码,来减少信息比特的估计数量,同时尝试最小化附加的排序操作。仿真结果表明,与传统的SCF译码相比,该SCF译码将重复SC译码的计算复杂度至少降低了27%。

关键词：分布式CRC 低复杂度极化码逐次抵消翻转译码

极化码的Reed-Solomon内核软判决译码

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长江信息通信 2024年第4期37卷 61-63页

作者：李炳槐郭铁梁王奎奎梧州学院电子与信息工程学院广西梧州543002

极化码的极化速率与译码复杂度取决于其采用的内核。本文考虑了具有Reed-Solomon内核的极化码的有效软判决译码问题,提出了一种基于分圆FFT算法的内核分解,结合逐次抵消译码算法能够实现对数似然比的近似最佳评估,并且降低了译码复杂度... 详细信息

极化码的极化速率与译码复杂度取决于其采用的内核。本文考虑了具有Reed-Solomon内核的极化码的有效软判决译码问题,提出了一种基于分圆FFT算法的内核分解,结合逐次抵消译码算法能够实现对数似然比的近似最佳评估,并且降低了译码复杂度。数值仿真结果表明,利用Reed-Solomon内核的极化码的软判决译码的帧错误率性能优于传统的Arikan内核的极化码。

关键词： Reed-Solomon内核极化码软判决逐次抵消译码

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Osteoporotic bone recovery by a bamboo-structured bioceramic with controlled release of hydroxyapatite nanoparticles

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Bioactive Materials 2022年第11期7卷 379-393页

作者： Rui Zhao tieliang Shang Bo Yuan Xiangdong Zhu Xingdong Zhang Xiao Yang National Engineering Research Center for Biomaterials Sichuan UniversityChengdu610064China

While most bone defects can be repaired spontaneously,the healing process can be complicated due to insuf-ficient bone regeneration when osteoporosis occurs.Synthetic materials that intrinsically stimulate bone for-mation without inclusion of exogenous cells or growth factors represent a highly desirable alternative to current grafting strategies for the management of osteoporotic defects.Herein,we developed a series of hydroxyapatite bioceramics composed of a microwhiskered scaffold(wHA)reinforced with multiple layers of releasable hy-droxyapatite nanoparticles(nHA).These novel bioceramics(nwHA)are tunable to optimize the loading amount of nHA for osteoporotic bone formation.The utility of nwHA bioceramics for the proliferation or differentiation of osteoporotic osteoblasts in vitro is demonstrated.A much more compelling response is seen when bioceramics are implanted in critical-sized femur defects in osteoporotic rats,as nwHA bioceramics promote significantly higher bone regeneration and delay adjacent bone loss.Moreover,the nwHA bioceramics loaded with a mod-erate amount of nHA can induce new bone formation with a higher degree of ossification and homogenization.Two types of osteogenesis inside the nwHA bioceramic pores were discovered for the first time,depending on the direction of growth of the new bone.The current study recommends that these tailored hybrid micro/nano-structured bioceramics represent promising candidates for osteoporotic bone repair.

关键词： Nano hydroxyapatite Bioceramics Osteogenesis Bone regeneration Osteoporosis

Crop water stress index for off-season greenhouse green peppers in liaoning, China

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International Journal of Agricultural and Biological Engineering 2014年第3期7卷 28-35页

作者： li Bo Wang tieliang Sun Jian College of Water Conservancy Shenyang Agricultural UniversityShenyang110866China

The crop water stress index(CWSI)is a complex instrument to effectively monitor the degree of water stress of crops and provides guidance for timely irrigation.In an experiment utilizing the CWSI with off-season green peppers planted in barrels in a greenhouse in liaoning Province,Northeast China,this study monitors the sub-indexes--such as canopy temperature,environmental factors and yield--determines the changing law of each constituent,achieves an empirical model as well as a baseline formula for the canopy temperature of the peppers with a sufficient water supply,and verifies the rationality of the formula with corresponding experimental data.The results obtained by using the CWSI show that the optimal time to determine the water deficit for off-season green peppers is at noon,by measuring the diurnal variation in the peppers with different water supplies.There is a nonlinear relationship between the yield and the average CWSI at the prime fruit-bearing period;moreover,the optimal time to supply water for off-season green peppers comes when the average water stress index ranges between 0.2 and 0.4 during the prime fruiting stage,thereby ensuring a high yield.

关键词： crop water stress index off-season green peppers in greenhouse high yield canopy temperature irrigation water deficit

Effects of straw size in buried straw layers on water movement in adjacent soil layers

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International Journal of Agricultural and Biological Engineering 2016年第2期9卷 74-84页

作者： Yao Mingze li Bo Wang tieliang Feng Xue College of Water Conservation Shenyang Agricultural UniversityShenyang 110866China

Deeply buried straw retention can improve the soil content of organic matter,its capacity for moisture preservation,the agroecological environment utilization efficiency of water resources,ensuring a stable crop yield;at the same time,the quantitative effects of deeply buried straw retention on soil moisture have a direct influence on the promotion and application of the technology.Using an infiltration and evaporation experiment of a one-dimensional soil column,the effects of straw size on the water content of the straw and the adjacent soil were evaluated when the straw was deeply buried in soil;the infiltration and evaporation features of different sized straw and its adjacent soil were analyzed;the hydraulic conductivity,sorptivity and saturated water content of the straw were obtained;in the end,the water distribution laws of straw and adjacent soil under the same conditions were concluded.The experiment was comprised of rod-shaped straw(RS),segment-shaped straw(SS)and filament-shaped straw(FS)to control treatment(CK).The results indicated that from the perspective of infiltration,the infiltration rate of filament-shape straw was the lowest at the stage of straw unsaturation.The hydraulic conductivities of rod-shaped,filament-shaped and segment-shaped straws are 4.01 mm/min,1.33 mm/min and 0.03 mm/min at the stage of straw and adjacent soil saturation,respectively.There is a strong effect on preventing infiltration from segment-shaped straw;with the help of the Philip model of long duration,the sorptivity of the soil with rod-shaped,filament-shaped and segment-shaped straws was 12.31 mm/min0.5,11.02 mm/min0.5 and 24.26 mm/min0.5 at the unsaturation stage,respectively.The segment-shape straw improved the water absorption capacity of the soil and straw column.The water retention capacities indicated that the saturated water contents of sandy loam,filament-shaped straw,segment-shaped straw and rod-shaped straw were 0.38 cm^(3)/cm^(3),0.29 cm^(3)/cm^(3),0.26 cm^(3)/cm^(3)and 0.13 cm^(3)/cm^(3),respectively.Addit

关键词： deeply buried straw straw size soil moisture infiltration evaporation water retention

结核分枝杆菌利福平和异烟肼耐药突变的快速分子诊断方法构建

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中国煤炭工业医学杂志 2024年第2期27卷 212-219页

作者：金聪王宇翔吴于婷王云宇李亚奇钱庆增胖铁良陈江坡华北理工大学公共卫生学院河北省唐山市063210 河北省职业卫生与安全协同创新中心廊坊诺道中科医学检验实验室有限公司

目的采用快速分子诊断方法中TaqMan荧光定量PCR技术,应用于利福平和异烟肼一线抗结核药物耐药基因的诊断中,评价其性能,建立高灵敏度、高特异度、高准确性并且快速的筛查方法,为结核分枝杆菌耐药性的诊断和治疗提供依据并探讨其应用价... 详细信息

目的采用快速分子诊断方法中TaqMan荧光定量PCR技术,应用于利福平和异烟肼一线抗结核药物耐药基因的诊断中,评价其性能,建立高灵敏度、高特异度、高准确性并且快速的筛查方法,为结核分枝杆菌耐药性的诊断和治疗提供依据并探讨其应用价值,努力改善耐药结核病的检测和可行性。方法本研究针对利福平ropB基因531位点突变和异烟肼katG基因315位点突变的特点,设计TaqMan-MGB引物和探针,通过反应条件优化,建立TaqMan荧光定量PCR方法;用克隆到pUC57载体上的阳性标准品及不同菌株评价该方法的特异性、灵敏度、重复性和精密度,采用甘油三酯、胆红素和血红素进行了干扰性实验。结果 TaqMan荧光定量PCR方法的检测限可达10copies/μl;在交叉干扰实验中,检测了5种常见呼吸道感染细菌国家标准菌株,均未检出,基因野生型和突变型探针特异性较好,不受其它基因干扰;批内、批间的CT值变异系数均小于5%,标准曲线R2=0.998,扩增效率均在90%以上;该反应迅速,检测时间为1h。结论本研究建立的TaqMan荧光定量PCR方法有助于及时发现结核分枝杆菌耐药情况,对结核病的耐药检测与后续治疗具有重要意义。

关键词：结核分枝杆菌 katG ropB 快速分子诊断 TaqMan荧光定量PCR