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蒸黄精粉末颜色与显微特征颜色及果糖含量的相关性研究

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时珍国医国药 2024年第5期35卷 1142-1146页

作者：邢玥陈鑫凤蔡梅超孔庆悦李浩然庄梓鸣赵鑫张学兰山东中医药大学药学院山东济南250355

目的探究蒸黄精粉末颜色、显微特征颜色及果糖含量的相关性。方法基于10批蒸黄精饮片样本,利用色差法测定粉末颜色值,利用显微成像技术测定显微特征颜色信息,采用HPLC-ELSD法测定果糖含量,运用Pearson相关性分析法分析粉末颜色、显微特... 详细信息

目的探究蒸黄精粉末颜色、显微特征颜色及果糖含量的相关性。方法基于10批蒸黄精饮片样本,利用色差法测定粉末颜色值,利用显微成像技术测定显微特征颜色信息,采用HPLC-ELSD法测定果糖含量,运用Pearson相关性分析法分析粉末颜色、显微特征颜色及果糖含量之间的相关性。结果蒸黄精粉末L^(*)值与表皮细胞和黏液细胞的L^(*)、E_(ab)^(*)值,导管的b^(*)、E_(ab)^(*)值及草酸钙针晶E_(ab)^(*)值呈显著正相关(P<0.05,P<0.01);蒸黄精粉末b^(*)值与草酸钙针晶b^(*)值呈显著正相关(P<0.01);蒸黄精粉末E_(ab)^(*)值与表皮细胞和黏液细胞的L^(*)、E_(ab)^(*)值和导管的b^(*)、E_(ab)^(*)值及草酸钙针晶E_(ab)^(*)值呈显著正相关(P<0.05,P<0.01);蒸黄精中果糖含量与其粉末、表皮细胞、黏液细胞的L^(*)、E_(ab)^(*)值及导管的b^(*)、E_(ab)^(*)值呈显著负相关(P<0.05,P<0.01)。结论蒸黄精粉末颜色和显微特征颜色及果糖含量之间存在一定的相关性,为蒸黄精饮片的质量评价提供了科学依据。

关键词：蒸黄精粉末颜色显微特征颜色色差法显微成像技术果糖 Pearson相关性分析

NHC-derived carbon-centered luminescent radicals with shortwavelength emission via suppression of Kasha's rule

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Science China Chemistry 2024年第8期67卷 2679-2685页

作者： Can chen xin Li xinhua Ouyang Ying-feng Han Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of the Ministry of Education Xi’an Key Laboratory of Functional Supramolecular Structure and MaterialsCollege of Chemistry and Materials ScienceNorthwest UniversityXi’an 710127China College of Material Engineering Fujian Agriculture and Forestry University Fuzhou 350108China

Luminescent organic radicals have garnered increasing attention owing to their versatile applications in sensing, imaging, and organic light-emitting diodes(OLEDs), attributed to their unique emission properties originating from the doublet spin ***, the natural narrow bandgap of organic free radicals typically limits their emission to the long-wavelength *** luminescent organic radicals with short-wavelength emission remains a significant challenge. Herein, a series of carbon-centered radicals with short-wavelength emission(383–476 nm) by combining N-heterocyclic carbenes with various polycyclic aromatic hydrocarbons(PAHs)(2-naphthyl, 2a~Ⅰ and 2b~Ⅰ;2-phenanthryl, 2a~Ⅱand 2b~Ⅱ;2-anthryl, 2a~Ⅲand 2b~Ⅲ;3-phenanthryl, 2a~Ⅳand 2b~Ⅳ). Theoretical calculations reveal that the introduction of PAHs significantly increases the ΔE_(D2-D1) in 2a^(Ⅰ–Ⅲ)and 2b^(Ⅰ–Ⅲ)compared to that in phenyl-derived radical congeners. Consequently, the internal transition from D2 to D1 is impeded, leading to a high yield of D2 emission and a suppressed Kasha's rule, thereby overcoming the limitations imposed by their narrow bandgap. For 2a~Ⅳ and 2b~Ⅳ, despite a moderately large ΔED2-D1value, the ΔED3-D1value exceeds 1 e V, indicating that their emission likely originates from the D3 state. Furthermore, we utilized 2a~Ⅲand 2b~Ⅲ as emissive materials in OLEDs,resulting in blue emissions with external quantum efficiencies of 7.5% and 6.5%, respectively.

关键词： N-heterocyclic carbenes luminescent organic molecules carbon-centered radicals short-wavelength emission

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Time-synchronous-averaging-spectrum based on super-resolution analysis and application in bearing fault signal identification

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第7期25卷 573-585页

作者： Zengle REN Yuan WANG Huiyue TANG xin'an chen Wei feng Guangdong Provincial Key Laboratory of Construction Robotics and Intelligent Construction Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen518055China Shenzhen EBORAIL Technology Co. Ltd.Shenzhen518038China National Supercomputing Center in Shenzhen Shenzhen518055China State Key Lab of Rail Traffic Control and Safety Beijing Jiaotong UniversityBeijing100044China University of Chinese Academy of Sciences Beijing100190China Shenzhen University of Advanced Technology Shenzhen518107China

Time-synchronous-averaging(TSA)is based on the idea of denoising by averaging,and it extracts the periodic components of a quasiperiodic signal and keeps the extracted waveform *** paper studies the mathematical properties of TSA,where three propositions are given to reveal the nature of *** paper also proposes a TSA-spectrum based on super-resolution analysis and it decomposes a signal without using any base *** contrast to discrete Fourier transform spectrum(DFT-spectrum),which is a spectrum in frequency domain,TSA-spectrum is a period-based spectrum,which can present more details of the cross effects between different periodic components of a quasiperiodic ***,a case study is carried out using bearing fault analysis to illustrate the performance of TSA-spectrum,where the rotation speed fluctuation of the shaft is estimated,which is about 0.12 ms *** extracted fault signals are presented and some insights are *** believe that this paper can provide new motivation for TSA-spectrum to be widely used in applications involving quasiperiodic signal processing(QSP).

关键词： Time-synchronous-averaging(TSA) Spectrum Quasiperiodic signal processing(QSP) Super-resolution analysis Bearingfaultdetection

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蒙古黄芪育苗基质的筛选及应用潜力初步评价

湖北农业科学 2024年第4期63卷 112-117页

作者：陈凤新田洪岭王俊红高芬山西大学中医药现代研究中心太原030006 山西大学化学化工学院太原030006 山西大学应用化学研究所太原030006 山西农业大学经济作物研究所山西汾阳032200

为筛选出适宜培育高质量幼苗的育苗基质,促进移栽蒙古黄芪(Astragalus membranaceus ***)的生产,以酒糟为主料,牛粪和沼渣为辅料,按不同体积比配制了6种有机复合基质,并对其理化性质,以及碱解氮、速效磷、速效钾的含量进行了测定。通过P... 详细信息

为筛选出适宜培育高质量幼苗的育苗基质,促进移栽蒙古黄芪(Astragalus membranaceus ***)的生产,以酒糟为主料,牛粪和沼渣为辅料,按不同体积比配制了6种有机复合基质,并对其理化性质,以及碱解氮、速效磷、速效钾的含量进行了测定。通过PLS-DA分析辅料对复合基质性质的影响,采用模糊评价法评估各复合基质肥效,进而筛选出基质F2(酒糟∶牛粪=60∶20)和Z2(酒糟∶沼渣=60∶20),将二者分别与纯土按体积比3∶7混合制成育苗基质后,通过发芽和幼苗生长试验评价应用潜力。结果表明,各有机复合基质理化性质基本符合常规基质要求,分别以牛粪和沼渣为辅料的两组复合基质,F2和Z2的肥效评价系数较高。混合育苗基质“F2+纯土”组的蒙古黄芪种子发芽率最高,且发芽势和发芽指数显著高于“Z2+纯土”组和对照组;同时,该组幼苗的整株长、株高和鲜重等指标也显著优于其他两组。由此可见,有机复合基质F2性能良好,与纯土混合后制成的育苗基质可用于蒙古黄芪优质幼苗的培育,具有较好的应用潜力。

关键词：育苗基质蒙古黄芪(Astragalus membranaceus var.mongholicus) 酒糟发芽与幼苗生长

Impact of Alcian blue and periodic acid Schiff expression on the prognosis of gastric signet ring cell carcinoma

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World Journal of Gastrointestinal Oncology 2024年第3期16卷 687-698页

作者： Juan Lin Zhu-feng chen Guo-Dong Guo xin chen Shengli Clinical Medical College Fujian Medical UniversityFuzhou 350001Fujian ProvinceChina Department of Pathology Fujian Provincial HospitalFuzhou 350001Fujian ProvinceChina Department of Internal Medicine Fujian Provincial HospitalFuzhou 350001Fujian ProvinceChina

BACKGROUND The Alcian blue(AB)and periodic acid Schiff(PAS)stains are representative mucus markers in gastric signet ring cell carcinoma(SRCC).They are low-cost special staining methods used to detect acidic mucus and neutral mucus,***,the clinical importance of the special combined AB and PAS stain is *** To investigate AB expression,PAS expression and the AB-to-PAS(A/P)ratio in gastric SRCC patients and to assess patient *** Paraffin-embedded sections from 83 patients with gastric SRCC were stained with AB and PAS,and signet ring cell positivity was assessed ***-histochemical staining for Ki67,protein 53(P53)and human epidermal growth factor receptor 2(HER2)was performed *** cancer-specific survival(CSS)rate was estimated via Kaplan-Meier *** proportional hazards models were used for univariate and multivariate survival *** Kaplan-Meier survival analysis revealed that the 3-year CSS rate was significantly greater in the high-PAS-expression subgroup than in the low-PAS-expression subgroup(P0.5 group(P=0.042).Univariate Cox regression analysis revealed that the factors affecting prognosis included tumor diameter,lymph node metastasis,vessel carcinoma embolus,tumor stage,the A/P ratio and the expression of Ki67,P53 and the *** multivariate regression analysis confirmed that low PAS expression[hazard ratio(HR)=3.809,95%confidence interval(CI):1.563-9.283,P=0.003]and large tumor diameter(HR=2.761,95%CI:1.086-7.020,P=0.033)were independent risk factors for poor *** A/P>0.5 is potentially a risk factor for prognosis,and low PAS expression is an independent risk factor in the prognosis of gastric *** expression and the A/P ratio could help in predicting the clinical prognosis of patients with SRCC.

关键词： Alcian blue Periodic acid-Schiff Prognosis Gastric Signet ring cell carcinoma

Preparation of Chemically Recyclable Poly(ether-alt-ester) by the Ring Opening Polymerization of Cyclic Monomers Synthesized by Coupling Glycolide and Epoxides

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Chinese Journal of Polymer Science 2024年第2期42卷 168-175,I0006页

作者： feng Ren Zhuang-Zhuang Liang Ming-xin Niu chen-Yang Hu Xuan Pang Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei230026China

Polyester and polyether are two key oxygenated polymers, and completely alternative sequence of poly(ester-alt-ether) could efficiently combine the advantages(including flexibility, degradability, etc.) of both segments. Currently, despite their copolymers could be synthesized from one-pot mixture of cyclic esters and epoxides, perfectly alternative microstructure is very challenging to realize and typically restricted to certain monomer pairs. Moving forward, synthesizing poly(ester-alt-ether) from commercially available and largescale monomers would be a significant advance. For example, successfully commercialized poly(glycolic acid)(PGA), which is not easily soluble in polymers due to its high crystallinity and is brittle and difficult to control the degradation cycle, would encounter a new paradigm if engineered into poly(ester-altether). In this work, starting from the design of monomer with hybrid structures, we successfully synthesized a series of 1,4-dioxan-2-one containing different substituents based on glycolide(GA) and epoxides using commercially available Salen-Cr(III) and PPNCl catalytic *** new monomers underwent ring-opening polymerization(ROP) to form a series of poly(ester-alt-ether) with perfectly alternating glycolic acid and propylene glycol repeat units under catalytic system of thiourea/base. The poly(ester-alt-ether) have significantly lower glass-transition temperature than PGA. Additionally, the poly(ester-alt-ether) can be chemically recovered to monomer using Sn(Oct)2 or 1,8-diazabicyclo[5.4.0]undecane-7-ene(DBU) as a catalyst in solution, thus establishing a closed-loop life cycle. From monomers derived from GA and epoxides, this work furnishes a novel strategy for the synthesis of poly(ester-alt-ether) with chemical recyclability.

关键词： Polyester Polyether Alternative copolymer Ring-opening polymerization

Effects of interstitial cluster mobility on dislocation loops evolution under irradiation of austenitic steel

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Nuclear Science and Techniques 2024年第8期35卷 69-78页

作者： xin‑Hua Yan Lu Sun Du Zhou Teng Xie Chang Peng Ye‑xin Yang Li chen Zhen‑feng Tong North China Electric Power University Beijing 102206China China Nuclear Power Operations Co. LtdShenzhen 518000China

The evolution of dislocation loops in austenitic steels irradiated with Fe~+is investigated using cluster dynamics(CD)simulations by developing a CD *** CD predictions are compared with experimental results in the *** number density and average diameter of the dislocation loops obtained from the CD simulations are in good agreement with the experimental data obtained from transmission electron microscopy(TEM)observations of Fe~+-irradiated Solution Annealed 304,Cold Worked 316,and HR3 austenitic steels in the *** CD simulation results demonstrate that the diffusion of in-cascade interstitial clusters plays a major role in the dislocation loop density and dislocation loop growth;in particular,for the HR3 austenitic steel,the CD model has verified the effect of temperature on the density and size of the dislocation loops.

关键词： Cluster dynamics Dislocation loops In-cascade interstitial clusters Austenitic steels

Iterative Signal Detection Based Soft Interference Cancellation for Satellite-Terrestrial Downlink NOMA Systems

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China Communications 2024年第8期21卷 249-263页

作者： Sun Meng Zhang Qi Yao Haipeng Gao Ran xin Xiangjun Tian feng feng Weiying chen Dong School of Electronic Engineering Beijing University of Posts and Telecommunications(BUPT)Beijing 100876China Beijing Key Laboratory of Space-Ground Interconnection and Convergence State Key Laboratory of Information Photonics and Optical CommunicationsSchool of Electronic EngineeringBeijing University of Posts and Telecommunications(BUPT)Beijing 100876China School of Information and Communication Engineering Beijing University of Posts and Telecommunications(BUPT)Beijing 100876China Beijing Institute of Technology Beijing 100081China Beihang University Beijing 100191China China Academy of Space Technology(CAST) Beijing 100094China

To improve the bit error rate(BER)performance of multi-user signal detection in satelliteterrestrial downlink non-orthogonal multiple access(NOMA)systems,an iterative signal detection algorithm based on soft interference cancellation with optimal power allocation is *** that power allocation has a significant impact on BER performance,the optimal power allocation is obtained by minimizing the average BER of NOMA *** to the allocated powers,successive interference cancellation(SIC)between NOMA users is performed in descending power *** each user,an iterative soft interference cancellation is performed,and soft symbol probabilities are calculated for soft *** improve detection accuracy and without increasing the complexity,the aforementioned algorithm is optimized by adding minimum mean square error(MMSE)signal estimation before detection,and in each iteration soft symbol probabilities are utilized for soft-decision of the current user and also for the update of soft interference of the previous *** results illustrate that the optimized algorithm ***-IDBSIC significantly outperforms joint multi-user detection and SIC detection by 7.57dB and 8.03dB in terms of BER performance.

关键词： non-orthogonal multiple access(NOMA) resource allocation satellite-terrestrial communication signal detection soft interference cancellation

Love wave propagation in one-dimensional piezoelectric quasicrystal multilayered nanoplates with surface effects

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Applied Mathematics and Mechanics(English Edition) 2024年第4期45卷 619-632页

作者： xin feng Liaoliang KE Yang GAO College of Science China Agricultural UniversityBeijing 100083China School of Mechanical Engineering Tianjin UniversityTianjin 300350China

The exact solutions for the propagation of Love waves in one-dimensional(1D)hexagonal piezoelectric quasicrystal(PQC)nanoplates with surface effects are *** electro-elastic model is developed to investigate the anti-plane strain problem of Love wave *** introducing three shape functions,the wave equations and electric balance equations are decoupled into three uncorrelated *** the boundary conditions of the top surface on the covering layer,the interlayer interface,and the matrix,a dispersive equation with the influence of multi-physical field coupling is provided.A surface PQC model is developed to investigate the surface effects on the propagation behaviors of Love waves in quasicrystal(QC)multilayered structures with nanoscale thicknesses.A novel dispersion relation for the PQC structure is derived in an explicit closed form according to the non-classical mechanical and electric boundary *** examples are given to reveal the effects of the boundary conditions,stacking sequence,characteristic scale,and phason fluctuation characteristics on the dispersion curves of Love waves propagating in PQC nanoplates with surface effects.

关键词： piezoelectric quasicrystal(PQC)material multilayered plate dispersion characteristic surface effect