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Soil and microbial C:N:P stoichiometries play vital roles in regulating P transformation in agricultural ecosystems:A review 被引量:5
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作者 Guanglei CHEN Jiahui YUAN +4 位作者 Shenqiang WANG Yuting LIANG Dengjun WANG Yiyong ZHU Yu WANG 《Pedosphere》 SCIE CAS CSCD 2024年第1期44-51,共8页
Stoichiometry plays a crucial role in biogeochemical cycles and can modulate soil nutrient availability and functions. In agricultural ecosystems,phosphorus(P) fertilizers(organic or chemical) are often applied to ach... Stoichiometry plays a crucial role in biogeochemical cycles and can modulate soil nutrient availability and functions. In agricultural ecosystems,phosphorus(P) fertilizers(organic or chemical) are often applied to achieve high crop yields. However, P is readily fixed by soil particles, leading to low P use efficiency. Therefore, understanding the role of carbon:nitrogen:P stoichiometries of soil and microorganisms in soil P transformation is of great significance for P management in agriculture. This paper provides a comprehensive review of the recent research on stoichiometry effect on soil P transformation in agricultural ecosystems. Soil microorganisms play an important role in the transformation of soil non-labile inorganic P to microbial biomass P by regulating microbial biomass stoichiometry. They also mobilize soil unavailable organic P into available P by changing ecoenzyme stoichiometry. Organic materials, such as manure and straw, play an important role in promoting the transformation of insoluble P into available P as well. Additionally, periphytic biofilms can reduce P loss from rice field ecosystems. Agricultural stoichiometries are different from those of natural ecosystems and thereby should receive more attention due to the influences of anthropogenic factors. Therefore, it is necessary to conduct further stoichiometry research on the soil biochemical mechanisms underlying P transformation in agricultural ecosystems. In conclusion, understanding stoichiometry impact on soil P transformation is crucial for P management in agricultural ecosystems. 展开更多
关键词 ecoenzyme microbial biomass microbial community MICROORGANISM p availability periphytic biofilm soil p transformation
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基于Transformer模型的5G P-IoT在高压设备测温中的应用
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作者 秦秉东 陈保豪 +4 位作者 刘博林 张国翊 朱海龙 索思亮 欧嘉俊 《广东电力》 北大核心 2025年第4期109-116,共8页
针对当前换流站一次设备温度监测中非接触式红外测温存在成本高、准确率低、时效性差等问题,提出一种面向高压场景的温度监控方案。该方案结合5G无源物联网(Passive Internet of Things,P-IoT)技术与Transformer模型。通过在高压设备关... 针对当前换流站一次设备温度监测中非接触式红外测温存在成本高、准确率低、时效性差等问题,提出一种面向高压场景的温度监控方案。该方案结合5G无源物联网(Passive Internet of Things,P-IoT)技术与Transformer模型。通过在高压设备关键部位部署无源温度传感器,利用反向散射通信技术实现低功耗数据传输,并借助5G网络将数据传输至边缘服务器处理。随后,采用基于Transformer的异常检测模型,通过多头注意力机制有效捕捉温度数据中的时序特征,结合最大池化操作实现对异常温度的准确识别与预警。实验结果表明,该方案在高电磁干扰环境下的传输成功率达到99.0%,在温度异常检测任务中的精度、召回率和F1值分别为98.7%、97.5%和96.9%,显著优于LSTM和GRU等传统时序模型。研究成果验证了所提方法在复杂高压场景下的适用性和稳定性,可为后续在更高电压等级的特高压设备中推广应用奠定技术基础。 展开更多
关键词 5G p-IoT 无源温度传感器 transformer模型 特高压设备 温度异常检测
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Effect of Nitrogen Fertilizers on Movement and Transformation of Phosphorus in an Acid Soil 被引量:17
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作者 DU Zhen-Yu ZHOU Jian-Min WANG Huo-Yan DU Chang-Wen CHEN Xiao-Qin 《Pedosphere》 SCIE CAS CSCD 2005年第4期424-431,共8页
The effects of two different nitrogen fertilizers (urea and NH4C1) with monocalcium phosphate (MCP) on the movement and transformation of fertilizer P in soil microsites along with soil pH changes at different dis... The effects of two different nitrogen fertilizers (urea and NH4C1) with monocalcium phosphate (MCP) on the movement and transformation of fertilizer P in soil microsites along with soil pH changes at different distances from the fertilizer application site were studied in an incubation experiment. A highly acidic red soil (Ultisol, pH 4.57) from south China with MCP fertilizer alone or in combination with NH4C1 or urea was added to the surface of soil cylinders and packed in wax blocks. After 7 and 28 days, the extraction and analysis of each 2 mm layer from the interface of the soil and fertilizer showed that added NH4C1 or urea did not change the movement distance of fertilizer P. However, P transformation was significantly affected (P 〈 0.05). After 7 days, at 0-8 mm distance from the fertilizer site the addition of urea significantly decreased the water-extractable P concentration; however, after 28 days the effect of N addition had disappeared. Also,at limited distances close to the fertilizer site NH4Cl application with MCP significantly increased acid-extractable P and available P, while with the addition of urea they significantly decreased. Compared with application of MCP alone,addition of urea significantly increased soil pH in fertilizer microsites, whereas the addition of NH4Cl significantly decreased soil pH. 展开更多
关键词 NH4CL p movement p transformation red soil UREA
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Effect of intestinal ischemia-reperfusion on expressions of endogenous basic fibroblast growth factor and transforming growth factor β in lung and its relation with lung repair 被引量:21
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作者 Xiao Bing Fu Yin Hui Yang Tong Zhu Sun Xiao Man Gu Li Xian Jiang Xiao Oing Sun Zhi Yong Sheng Research Laboratory,304th Hospital of PLA,Beijing 100037,China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2000年第3期353-355,共3页
AIM To study the changes of endogenoustransforming growth factor β(TGFβ)and basicfibroblast growth factor(bFGF)in lung followingintestinal ischemia and reperfusion injury andtheir effects on lung injury and repair.M... AIM To study the changes of endogenoustransforming growth factor β(TGFβ)and basicfibroblast growth factor(bFGF)in lung followingintestinal ischemia and reperfusion injury andtheir effects on lung injury and repair.METHODS Sixty Wistar rats were divided intofive groups,which underwent sham-operation,ischemia(45 minutes),and reperfusion(6,24and 48 hours,respectively)after ischemia(45minutes).Immunohistochemical method wasused to observe the localization and amounts ofboth growth factors.RESULTS Positive signals of both growthfactors could be found in normal lung,mainly inalveolar cells and endothelial cells of vein.Afterischemia and reperfusion insult,expressions ofboth growth factors were increased and theiramounts at 6 hours were larger than those ofnormal control or of 24 and 48 hours after insult.CONCLUSION The endogenous bFGF and TGF βexpression appears to be up-regulated in thelung following intestinal ischemia andreperfusion,suggesting that both growth factorsmay be involved in the process of lung injury andrepair. 展开更多
关键词 LUNG intestinal ischemiareperfusion injury basic FIBROBLAST GROWTH FACTOR transformING GROWTH FACTOR p
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中碳高硅Q&P钢马氏体相变动力学 被引量:4
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作者 刘曼 周明星 +2 位作者 陈振业 尹伟凡 徐光 《钢铁》 北大核心 2025年第3期117-124,共8页
目前常用经典的K-M(Koistinen-Marburger)模型描述钢的马氏体相变动力学,但模型的准确性与钢种成分密切相关。基于不同冷却速率的淬火试验,采用膨胀法、金相法研究了常见中碳高硅淬火-配分(Q&P)钢的马氏体相变动力学规律,并基于传统... 目前常用经典的K-M(Koistinen-Marburger)模型描述钢的马氏体相变动力学,但模型的准确性与钢种成分密切相关。基于不同冷却速率的淬火试验,采用膨胀法、金相法研究了常见中碳高硅淬火-配分(Q&P)钢的马氏体相变动力学规律,并基于传统K-M模型建立了适用于中碳高硅Q&P钢的改进马氏体相变动力学模型,并对其进行了验证。结果表明,不同冷却速率下,中碳高硅Q&P钢的马氏体相变动力学曲线呈“S”形,而不是“C”形,相变过程可分为开始相变的加速期、中间相变的高速期和最后相变的减速期,这可能是马氏体的自回火现象引起的。此外,靠近马氏体相变开始温度形成的马氏体较为粗大,此时温度较高,碳从过饱和马氏体板条扩散到周围未转化的奥氏体中,奥氏体碳富集增加了残余奥氏体的稳定性,使得过冷度需要进一步增加才能继续发生马氏体相变,从而降低了残余奥氏体的马氏体相变开始温度。马氏体相变动力学方程指数β为1~2的常数。β值对淬火温度的敏感性取决于钢的碳含量。碳含量升高时,β值对淬火温度的敏感性显著降低,基本可以忽略。速率参数α为淬火温度的3次多项式函数,随着冷却速率的增加,速率参数α逐渐降低,这表明马氏体相变可能是一个与时间有关的相变;而方程指数β逐渐增加,这与奥氏体塑性调节对马氏体相变的抑制作用有关。改进K-M模型考虑了马氏体相变的瞬时动力学特性,与试验数据的匹配度较传统K-M模型更好。 展开更多
关键词 中碳高硅Q&p 马氏体相变 动力学模型 速率参数 方程指数 改进K-M模型 高级钢 TRIp效应
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Reductive transformation of p-nitrotoluene by a new iron-fly ash packing 被引量:1
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作者 Baizhen Yu Ruofei Jin +1 位作者 Guangfei Liu Jiti Zhou 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2015年第11期31-36,共6页
A new iron-fly ash packing was studied for reductive transformation of p-nitrotoluene. The packing was made of iron, fly ash and kaolin with the mass ratio of 36:7:2. A reactor was designed to investigate the long-t... A new iron-fly ash packing was studied for reductive transformation of p-nitrotoluene. The packing was made of iron, fly ash and kaolin with the mass ratio of 36:7:2. A reactor was designed to investigate the long-term performance of the packing. The results showed that the reduction of p-nitrotoluene increased with decreasing pH, because the reduction potential of reaction increased with the concentration of H+. The pH was one of the key factors impacting the reductive transformation of p-nitrotoluene. Comparing iron-activated carbon packing with the new iron-fly ash packing, the reduction efficiencies were respectively 76.61% and 75.36% after20 days. The reduction efficiency for both was around 50% at 40 days. It was evident that these two kinds of packing had no significant difference in their capability for p-nitrotoluene reductive transformation. Compared with iron-activated carbon, the new iron-fly ash packing had obvious advantages in terms of manufacturing costs and environmental pollution degradation. This study showed that the new iron-fly ash packing had good performance in reductive transformation of nitrotoluene compounds. 展开更多
关键词 New iron-fly ash packing Reactor Reductive transformation p-Nitrotoluene
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P-Wave Detection Combining Entropic Criterion and Wavelet Transform 被引量:1
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作者 Sawsan Rekik Noureddinne Ellouze 《Journal of Signal and Information Processing》 2015年第3期217-226,共10页
The objective of this paper is to develop an efficient P wave detection method in electrocardiogram (ECG) using the local entropy criterion (EC) and wavelet transform (WT) modulus maxima. The detection of P wave relat... The objective of this paper is to develop an efficient P wave detection method in electrocardiogram (ECG) using the local entropy criterion (EC) and wavelet transform (WT) modulus maxima. The detection of P wave relates to the diagnosis of many heart diseases and it is also a difficult point during the ECG signal detection. Determining the position of a P-wave is complicated due to the low amplitude, the ambiguous and changing form of the complex. In a first step, QRS complexes are detected using the pan-Tompkins method. Then, we look for the best position of the analysis window and the value of the most appropriate width to the P wave. Finally, the determination of P wave peaks, as well as their onsets and offsets. The method has been validated using ECG-recordings with a wide variety of P-wave morphologies from MIT-BIH Arrhythmia and QT database. The P-wave method obtains a sensitivity of 99.87% and a positive predictivity of 98.04% over the MIT-BIH Arrhythmia, while for the QT, sensitivity and predictivity over 99.8% are attained. 展开更多
关键词 ECG p-WAVE Entropy WAVELET transform MODULUS MAXIMA
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2维G-P方程的高阶快速保能量方法
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作者 陈杰 孙建强 《江西师范大学学报(自然科学版)》 北大核心 2025年第5期519-525,共7页
该文将2维G-P方程转化成无限维哈密尔顿系统,利用傅里叶拟谱方法和平均向量场方法对方程分别进行空间和时间离散得到方程的数值离散格式,基于快速傅里叶变换分解谱矩阵得到了2维G-P方程的快速保能量计算格式,利用新的保能量格式数值模... 该文将2维G-P方程转化成无限维哈密尔顿系统,利用傅里叶拟谱方法和平均向量场方法对方程分别进行空间和时间离散得到方程的数值离散格式,基于快速傅里叶变换分解谱矩阵得到了2维G-P方程的快速保能量计算格式,利用新的保能量格式数值模拟方程孤立波演化行为,并分析了新格式的保能量守恒特性. 展开更多
关键词 平均向量场方法 2维G-p方程 傅里叶拟谱方法 快速傅里叶变换
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On the Proximate Type of Analytic Function Represented by Laplace-Stieltjes Transformation 被引量:3
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作者 Wanchun LU 《Journal of Mathematical Research with Applications》 CSCD 2015年第1期97-102,共6页
In present paper, we study precisely the growth of analytic functions defined by zero order Laplace-Stieltjes transformation converging in right plane. The coefficient characterizations of generalized logarithmic p-ty... In present paper, we study precisely the growth of analytic functions defined by zero order Laplace-Stieltjes transformation converging in right plane. The coefficient characterizations of generalized logarithmic p-type and generalized lower logarithmic p-type are obtained, which improve the results of logarithmic type and lower logarithmic type. 展开更多
关键词 Laplace-Stieltjes transform zero order logarithmic p-type lower logarithmic p-type
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Deghosting towed streamer data in τ/p domain based on rough sea surface reflectivity 被引量:16
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作者 张兴岩 潘冬明 +3 位作者 史文英 方中于 但志伟 张立霞 《Applied Geophysics》 SCIE CSCD 2015年第4期573-584,629,共13页
Currently, the deghosting of towed streamer seismic data assumes a flat sea level and a sea-surface reflection coefficient of-1; this decreases the precision of deghosting. A new method that considers the rough sea su... Currently, the deghosting of towed streamer seismic data assumes a flat sea level and a sea-surface reflection coefficient of-1; this decreases the precision of deghosting. A new method that considers the rough sea surface is proposed to suppress ghost reflections. The proposed deghosting method obtains the rough sea surface reflection coefficient using Gaussian statistics, and calculates the optimized deghosting operator in the r/p domain. The proposed method is closer to the actual sea conditions, offers an improved deghosting operator, removes the ghost reflections from marine towed seismic data, widens the bandwidth and restores the low-frequency information, and finally improves the signal-to- noise ratio and resolution of the seismic data. 展开更多
关键词 deghosting τ/p transform submarine tow cable sea surface reflection coefficient
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A Wavelet Transform Method to Detect P and S-Phases in Three Component Seismic Data
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作者 Salam Al-Hashmi Adrian Rawlins Frank Vernon 《Open Journal of Earthquake Research》 2013年第1期1-20,共20页
The discrete time wavelet transform has been used to develop software that detects seismic P and S-phases. The detection algorithm is based on the enhanced amplitude and polarization information provided by the wavele... The discrete time wavelet transform has been used to develop software that detects seismic P and S-phases. The detection algorithm is based on the enhanced amplitude and polarization information provided by the wavelet transform coefficients of the raw seismic data. The algorithm detects phases, determines arrival times and indicates the seismic event direction from three component seismic data that represents the ground displacement in three orthogonal directions. The essential concept is that strong features of the seismic signal are present in the wavelet coefficients across several scales of time and direction. The P-phase is detected by generating a function using polarization information while S-phase is detected by generating a function based on the transverse to radial amplitude ratio. These functions are shown to be very effective metrics in detecting P and S-phases and for determining their arrival times for low signal-to-noise arrivals. Results are compared with arrival times obtained by a human analyst as well as with a standard STA/LTA algorithm from local and regional earthquakes and found to be consistent. 展开更多
关键词 Discrete Time WAVELET transform p and S-phases Automatic Detection Rectilinearity Function
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面阵对称翻转变换用于F-P微小角度测量系统 被引量:1
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作者 吴晨光 沈小燕 周世南 《中国测试》 北大核心 2025年第1期111-118,共8页
法布里珀罗(F-P)标准具应用于位移和角度测量时,其干涉成像同心圆环圆心坐标的准确计算对测量结果具有关键影响。针对面阵CCD传感器上干涉成像同心圆环在移动时存在的误差,利用干涉成像同心圆环有效信息,提出一种面阵像元正反细分的对... 法布里珀罗(F-P)标准具应用于位移和角度测量时,其干涉成像同心圆环圆心坐标的准确计算对测量结果具有关键影响。针对面阵CCD传感器上干涉成像同心圆环在移动时存在的误差,利用干涉成像同心圆环有效信息,提出一种面阵像元正反细分的对称翻转算法,在理论分析的基础上进行算法和实验验证。将该算法应用于F-P微小角度测量系统并进行比对实验研究。实验结果表明该算法可将圆心坐标标准差减小至0.0028个像素单位;在±150″测量范围内,F-P微小角度测量系统的测量值与ELCOMAT HR自准直仪两者的示值误差不大于0.38″,经拟合修正后两者示值误差不大于0.06″,测量准确度得到有效提高。 展开更多
关键词 F-p标准具 对称翻转变换 像元平滑细分 圆心坐标计算 微小角度测量
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Relativistic effect of pseudospin symmetry and tensor coupling on the Mie-type potential via Laplace transformation method
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作者 M.Eshghi S.M.Ikhdair 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第12期44-49,共6页
A relativistic Mie-type potential for spin-1/2 particles is studied. The Dirac Hamiltonian contains a scalar S(r) and a vector V(r) Mie-type potential in the radial coordinates, as well as a tensor potential U(r... A relativistic Mie-type potential for spin-1/2 particles is studied. The Dirac Hamiltonian contains a scalar S(r) and a vector V(r) Mie-type potential in the radial coordinates, as well as a tensor potential U(r) in the form of Coulomb potential. In the pseudospin(p-spin) symmetry setting Σ = Cps and Δ = V(r), an analytical solution for exact bound states of the corresponding Dirac equation is found. The eigenenergies and normalized wave functions are presented and particular cases are discussed with any arbitrary spin–orbit coupling number κ. Special attention is devoted to the caseΣ = 0 for which p-spin symmetry is exact. The Laplace transform approach(LTA) is used in our calculations. Some numerical results are obtained and compared with those of other methods. 展开更多
关键词 Dirac equation Mie-type potential Laplace transform approach tensor interaction p-spin symmetry
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Power Transformer Fault Diagnosis Using Fuzzy Reasoning Spiking Neural P Systems 被引量:1
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作者 Yousif Yahya Ai Qian Adel Yahya 《Journal of Intelligent Learning Systems and Applications》 2016年第4期77-91,共15页
This paper presents an intelligent technique to fault diagnosis of power transformers dissolved and free gas analysis (DGA). Fuzzy Reasoning Spiking neural P systems (FRSN P systems) as a membrane computing with distr... This paper presents an intelligent technique to fault diagnosis of power transformers dissolved and free gas analysis (DGA). Fuzzy Reasoning Spiking neural P systems (FRSN P systems) as a membrane computing with distributed parallel computing model is powerful and suitable graphical approach model in fuzzy diagnosis knowledge. In a sense this feature is required for establishing the power transformers faults identifications and capturing knowledge implicitly during the learning stage, using linguistic variables, membership functions with “low”, “medium”, and “high” descriptions for each gas signature, and inference rule base. Membership functions are used to translate judgments into numerical expression by fuzzy numbers. The performance method is analyzed in terms for four gas ratio (IEC 60599) signature as input data of FRSN P systems. Test case results evaluate that the proposals method for power transformer fault diagnosis can significantly improve the diagnosis accuracy power transformer. 展开更多
关键词 Dissolved Gas Analysis Fault Diagnosis Fuzzy Reasoning power transformer Faults Spiking Neural p System
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EFFECTS OF TRANSFORMING GROWTH FACTOR β AND RECOMBINANT HUMAN BONE MORPHOGENETIC PROTEIN 2 ON HUMAN PERIODONTAL LIGAMENT FIBROBLASTS
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作者 司晓辉 刘正 《Journal of Shanghai Second Medical University(Foreign Language Edition)》 2001年第1期36-40,共5页
Objective To evaluate the effects of transforming growth factor β(TGF-β) and recombinant human bone morphogenetic protein 2 (rhBMP2) on human periodontal ligament fibroblasts (HPDLFs). Methods HPDLFs were done prima... Objective To evaluate the effects of transforming growth factor β(TGF-β) and recombinant human bone morphogenetic protein 2 (rhBMP2) on human periodontal ligament fibroblasts (HPDLFs). Methods HPDLFs were done primary culture to detect the distinct concentrations of TGF-P and rhBMF2 on its proliferation, alkaline phosphatase (ALP) activity, osteocalcin (OC) synthesis and formation of the minerali-zed nodules, respectively. Results TGF-β (5~100ng/ml) significantly stimulated the proliferation of HPDLFs. The ALP activity of HPDLFs was evaluated evidently by 5ng/ml TGF-β. TGF-β( 0. 5 ~ 100ng/ml) had no effects on OC synthesis and formation of the mineralized nodules of HPDLFs. rhBMP2 (0. 25~2mg/ ml) had no remarkable effect on the proliferation of HPDLFs. The ALP activity, OC synthesis and forma-tion of the mineralized nodules of HPDLFs were significantly stimulated by 0. 5~ 2mg /ml rhBMP2. Conclusion The effects of TGF-β and rhBMP2 on HPDLFs are dose-dependent. TGF-P can stimulate HPDLFs to express the early marker of osteoblastic phenotype, and it lacks the ability to promote maturation of the osteogenic phenotype. rhBMP2 can not only stimulate the expression but also promote the maturation of osteoblas-tic phenotype of HPDLFs. 展开更多
关键词 transforming growth factor precombinant human bone morphogenetic protein 2human periodontal ligament fibroblastsalkaline phosphataseosteocalcin mineralization
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PPTA多孔膜及其复合材料的制备与性能研究
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作者 王文宇 孙晓玲 +1 位作者 王可濛 孔海娟 《合成纤维工业》 2025年第1期1-6,共6页
以聚乙烯吡咯烷酮(PVP)为致孔剂,以聚四氟乙烯微孔滤膜为基底,通过相转化法制备聚对苯二甲酰对苯二胺(PPTA)多孔膜,研究PVP含量对PPTA多孔膜的孔隙率、微观形貌、浸润性及力学性能的影响;以PPTA多孔膜作为增强相,采用真空导入法制备PPT... 以聚乙烯吡咯烷酮(PVP)为致孔剂,以聚四氟乙烯微孔滤膜为基底,通过相转化法制备聚对苯二甲酰对苯二胺(PPTA)多孔膜,研究PVP含量对PPTA多孔膜的孔隙率、微观形貌、浸润性及力学性能的影响;以PPTA多孔膜作为增强相,采用真空导入法制备PPTA多孔膜/环氧树脂复合材料,研究环氧树脂与PPTA多孔膜的浸润性及复合材料的力学性能。结果表明:随着PVP含量的增加,PPTA多孔膜的孔隙率增加,PVP质量分数为6%时多孔膜的孔隙率达61.2%,继续提高PVP含量,多孔膜的孔隙率变化不大,PVP质量分数为5%时PPTA多孔膜表面孔隙较为均匀,孔结构也较为均匀;随着PVP含量的增加,PPTA多孔膜与水的接触角逐渐减小,表面自由能逐渐增加,PVP质量分数为6%时接触角最小,为21.2°,表面自由能最大,为70.5 mJ/m^(2);PVP质量分数为5%~6%时,PPTA多孔膜与环氧树脂的浸润性良好;随着PVP含量的增加,PPTA多孔膜的拉伸强度逐渐降低,PPTA多孔膜增强复合材料的拉伸强度先升后降,PVP质量分数为5%时PPTA多孔膜及其增强复合材料具有优良的综合性能,多孔膜的拉伸强度为1.7 MPa,PPTA多孔膜增强复合材料的拉伸强度为468.3 MPa。 展开更多
关键词 聚对苯二甲酰对苯二胺 多孔膜 致孔剂 相转化法 复合材料 力学性能 浸润性能
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智能P&ID技术在油气勘探开发上的应用
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作者 任秋月 刘燕 +1 位作者 冯家翔 刘赫宇 《化工管理》 2025年第17期93-96,共4页
随着全球能源需求的增长,油气勘探开发行业面临提升生产效率与降低运营成本的双重挑战。传统的P&ID方法已不足以满足现代油气田的管理需求。智能P&ID(管道及仪表流程图)技术,作为传统P&ID的升级,引入了信息技术和数字化工具... 随着全球能源需求的增长,油气勘探开发行业面临提升生产效率与降低运营成本的双重挑战。传统的P&ID方法已不足以满足现代油气田的管理需求。智能P&ID(管道及仪表流程图)技术,作为传统P&ID的升级,引入了信息技术和数字化工具,实现了工艺流程的动态化和智能化。文章探讨了智能P&ID技术在油气勘探开发中的应用,包括其核心功能、实时数据集成以及设备管理优化。智能P&ID技术通过提高数据集成与分析能力,增强了生产过程的安全性和环境保护,同时支持企业数字化转型,为油气行业带来了革新性的改变。 展开更多
关键词 智能p&ID 油气勘探 数据集成 设备管理 数字化转型
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应用OVT域体τ-p变换提高地震资料信噪比 被引量:11
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作者 李飞 段文胜 +2 位作者 赵锐锐 罗莉莉 党青宁 《石油地球物理勘探》 EI CSCD 北大核心 2015年第3期418-423,2,共6页
体τ-p变换技术将常规二维τ-p变换去噪方法应用于三维叠后数据体,可显著提高信噪比。OVT(Offset Vector Tile)域道集可延展至全工区的单次覆盖特性,便于在叠前应用体τ-p变换技术。在OVT域将体τ-p变换技术应用于TG地区实际低信噪比数... 体τ-p变换技术将常规二维τ-p变换去噪方法应用于三维叠后数据体,可显著提高信噪比。OVT(Offset Vector Tile)域道集可延展至全工区的单次覆盖特性,便于在叠前应用体τ-p变换技术。在OVT域将体τ-p变换技术应用于TG地区实际低信噪比数据,并与常规3D-RNA技术进行对比,结果表明:无论是在去噪未实施偏移前还是在去噪实施偏移后,体τ-p变换技术压制随机噪声、提高信噪比的效果均明显优于3D-RNA技术,因此它是一种提高低信噪比地区地震资料成像品质的有效手段。 展开更多
关键词 体τ-p变换 OVT域 3D-RNA 地震数据处理 去噪
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线性同相轴波场分离的高分辨率τ-p变换法 被引量:32
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作者 王维红 首皓 +1 位作者 刘洪 孙兆海 《地球物理学进展》 CSCD 北大核心 2006年第1期74-78,共5页
基于最小二乘τ-p变换和τ-p域模型稀疏分布的假设,本文给出高分辨率τ-p变换的推导及其模型空间域的离散采样公式,同时给出了保振幅线性同相轴波场分离的算法流程.在求解本文给出的高分辨率τ-p正变换时,由于待求解的矩阵不具备最小平... 基于最小二乘τ-p变换和τ-p域模型稀疏分布的假设,本文给出高分辨率τ-p变换的推导及其模型空间域的离散采样公式,同时给出了保振幅线性同相轴波场分离的算法流程.在求解本文给出的高分辨率τ-p正变换时,由于待求解的矩阵不具备最小平方法所具有的Toeplitz结构,故采用Cholesky分解法进行计算.本文模拟了井间地震和阵列声波测井中的Stoneley上下行波的分离算法过程,高分辨率正反τ-p变换且滤波所得结果显示本文算法误差小和保振幅的特点.对于在τ-p域距离很近或时间域同相轴近于水平的线性波场,高分辨率算法的聚焦作用使得所分离波场畸变小,体现本文算法精度高的优点.理论模型试算表明本文给出的高分辨率τ-p变换线性波场分离算法具有稳定性、精度高和保振幅的特点. 展开更多
关键词 τ-p变换(线性Radon变换) 高分辨率 CHOLESKY分解 波场分离 稀疏分布 线性同相轴
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BCL、RIP细胞凋亡基因向小麦中的导入和赤霉病抗性鉴定 被引量:12
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作者 叶兴国 Shirley Sato +4 位作者 徐惠君 杜丽璞 黄益洪 陆维忠 Tom Clemente 《作物学报》 CAS CSCD 北大核心 2005年第11期1389-1393,共5页
利用农杆菌介导法将BCL和RIP 2个与细胞凋亡有关的基因分别导人了小麦品种扬麦10号和Bobwhite,转化效率分别为1.60%和1.25%。Southern检测结果表明,细胞凋亡基因已稳定整合到小麦染色体上,多数植株为单拷贝整合。Northern检测结... 利用农杆菌介导法将BCL和RIP 2个与细胞凋亡有关的基因分别导人了小麦品种扬麦10号和Bobwhite,转化效率分别为1.60%和1.25%。Southern检测结果表明,细胞凋亡基因已稳定整合到小麦染色体上,多数植株为单拷贝整合。Northern检测结果表明,细胞凋亡基因能够在小麦遗传背景中高水平转录为RNA。转基因植株T1代分离比例为2.11~2.33:1,表明外源基因在后代中能够稳定遗传。BCL转基因植株和RIP转基因植株对赤霉病均表现出一定抗性,其中BCL-20、BCL-21、RIP-8、RIP-18等15个T1代植株的小穗发病率为5.6%~16.1%,可望进一步培育抗赤霉病小麦新材料。 展开更多
关键词 小麦 BCL基因 RIp基因 转化 赤霉病
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