检索结果-南通市图书馆

Journal of Natural Gas Chemistry 2006年第1期15卷 45-51页

作者： Feifei sun Shunhe Zhong department of Chemistry School of Science Tianjin University Tianjin 300072 China College of Chemical Engineering and Technology Tianjin University Tianjin 300072 China

The supported Au/TiO2 and Au/TiO2-SiO2 catalysts were prepared by deposition precipitation method. The TPD study reveals that propylene oxide competes with propylene to be adsorbed on the same adsorptive center-Ti^n＋ site on the surface of the catalyst and that the adisorbing capacity of the catalyst for propylene oxide is larger than that for propylene. Catalytic behavior for propylene epoxidation with H2 and O2 was tested in a micro-reactor. Under typical conditions, the selectivity for propylene oxide is over 87%. The TG curves show that PO successive oxidation cause carbon deposition on the active center and deactivation of the Au catalysts. Because the amounts of Tin＋ site decrease significantly, and consequently the separation between Ti^n＋ sites increases, the Au/TiO2-SiO2 catalyst is more stable than Au/TiO2.

关键词： Au/TiO2 Au/TiO2-SiO2 propylene propylene oxide epoxidation catalyst stability

在线全文

学校读者我要写书评

暂无评论

基于深度学习的跳绳姿态评估系统研究

电子设计工程 2025年第05期33卷 1-7页

作者：丁瀚孙少明孙怡宁张子康彭伟中国科学技术大学中国科学院合肥物质科学研究院中科合肥技术创新工程院

为解决青少年日常跳绳中可能存在的问题，规范其训练动作以降低受伤风险，提出了一种跳绳姿态检测与评估系统。该系统包含两个检测评估机制：机制1基于Attention-MLP神经网络模型进行标准化检测评估；机制2则对监测时段内高维跳绳特征... 详细信息

为解决青少年日常跳绳中可能存在的问题，规范其训练动作以降低受伤风险，提出了一种跳绳姿态检测与评估系统。该系统包含两个检测评估机制：机制1基于Attention-MLP神经网络模型进行标准化检测评估；机制2则对监测时段内高维跳绳特征数据进行提取与分析。系统包括数据获取、数据预处理以及跳绳姿态检测与评估。在数据预处理部分，文中进行了3种滤波算法的比较实验，结果表明，卡尔曼滤波对于跳绳的二维骨骼点数据平滑效果更佳。在标准化评估模块中，基于跳绳特征的数据集，搭建了Attention-MLP模型，并将其与常用的识别算法MLP、LSTM、CNN进行了实验对比。实验结果表明，Attention-MLP模型表现更为出色，准确率可达99.38%。

关键词：跳绳动作检测评估骨骼点识别数据滤波深度学习

自主D1规格与API CK-4规格对比分析及自主复合剂技术开发

在线全文

学校读者我要写书评

暂无评论

石油炼制与化工 2025年第1期56卷 160-166页

作者：孙文斌张倩黄作鑫张峰中石化石油化工科学研究院有限公司北京100083

综合对比了柴油机油我国自主D1规格和API CK-4规格在理化性能指标、发动机台架试验性能指标等方面的差异;进而,结合中国石化自主开发的符合API CK-4规格的柴油机油复合剂技术(RIPP C0010)在两种规格发动机台架试验中的评价结果,系统分... 详细信息

综合对比了柴油机油我国自主D1规格和API CK-4规格在理化性能指标、发动机台架试验性能指标等方面的差异;进而,结合中国石化自主开发的符合API CK-4规格的柴油机油复合剂技术(RIPP C0010)在两种规格发动机台架试验中的评价结果,系统分析D1规格与API CK-4规格的相关性,以及RIPP C0010柴油机油技术对国产发动机的适用性。结果表明:除柴油喷嘴剪切后高温高剪切黏度存在差异外,D1规格与API CK-4规格的其他理化性能指标,包括高低温运动黏度、蒸发损失率、高温抗腐蚀性、抗泡性能、元素含量等均基本相同;D1规格的4种台架试验均可以评价多项油品性能,如抗氧化性能、清净性能、分散性能、抗磨性能等,实现了API CK-4规格10种台架试验的评价效果,但仍需进一步完善其基础油互换规则和黏度级别延伸规则;行车试验结果表明,自主研发RIPP C0010柴油机油可满足重载柴油发动机60000 km换油周期使用要求。

关键词：柴油机油 D1规格 API CK-4规格发动机台架试验

在线全文

学校读者我要写书评

暂无评论

输油站场碳排放核算与碳夹点分析

化工环保 2025年第1期45卷 127-133页

作者：孟瑶孙东旭刘飞胡志勇辽宁石油化工大学石油天然气工程学院辽宁抚顺113001

探讨了东北某输油站场的碳排放核算方法,并结合碳夹点分析法提出了能源结构的调整方案,着重研究了可再生能源对高碳排放能源的替代,从而减少碳排放。碳排放核算结果表明,输油站场温室气体的年排放量约为605705.87 t CO_(2)e,其中电力消... 详细信息

探讨了东北某输油站场的碳排放核算方法,并结合碳夹点分析法提出了能源结构的调整方案,着重研究了可再生能源对高碳排放能源的替代,从而减少碳排放。碳排放核算结果表明,输油站场温室气体的年排放量约为605705.87 t CO_(2)e,其中电力消耗产生的温室气体排放量在高碳排放能源中占比最高,超过94%。碳夹点分析结果表明:在高碳排放能源减排10%的限制下,采用最小可再生能源量方案时,能源结构为电力80.10%、热力4.01%、天然气3.95%、煤2.40%、可再生能源9.54%,可再生能源量为14716.36 tce;采用最大可再生能源量方案时,能源结构为电力85.66%、可再生能源14.35%,可再生能源量为22131.76 tce;在此基础上做进一步分析,可得到各部门的能源分配方案。

关键词：碳足迹碳减排输油站场碳夹点分析

An ultra-sensitive metasurface biosensor for instant cancer detection based on terahertz spectra

在线全文

学校读者我要写书评

暂无评论

Nano Research 2023年第5期16卷 7304-7311页

作者： Peiliang Wang Jing Lou Yun Yu Lang sun Lan sun Guangyou Fang Chao Chang Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100094China Innovation Laboratory of Terahertz Biophysics National Innovation Institute of Defense TechnologyBeijing 100071China The Key Laboratory of Electromagnetic Radiation and Sensing Technology Chinese Academy of SciencesBeijing 100190China School of Electronic Electrical and Communication EngineeringUniversity of Chinese Academy of SciencesBeijing 100049China Air and Missile defense College Air Force Engineering UniversityXi’an 710051China Institute of Acupuncture and Moxibustion China Academy of Chinese Medical SciencesBeijing 100007China School of Psychological and Cognitive Sciences Beijing Key Laboratory of Behavior and Mental HealthPeking UniversityBeijing 100871China School of Life Science and Technology Xi’an Jiaotong UniversityXi’an 710049China

Metasurface biosensors have become the core label-free and rapid-detection technology in *** cancer and brain cancer are the first leading causes of cancer death among adults and adolescents,respectively,where poor early diagnosis results from expensive detection costs and time *** tackle the above problems,here,we introduce a terahertzdomain metasurface biosensor for cancer diagnosis,relying on a perfectly symmetrical periodic surface structure,which significantly exhibits polarization-insensitivity at 2.05 THz and the high-sensitivity of 504 GHz/RIU(RIU=refractive index unit).According to the frequency shifts and transmittance variations,four cell types are successfully distinguished from each *** minimum number of cells is required for thousands of cells to display the differences of spectra,which is 1/30 of clinical ***,the results were consistent with pathological results(the gold standard in clinic)by Gaussian curve *** proposed biosensor has really achieved the characterization of cells in normal and cancerous *** detection strategy dramatically reduced the cost of detection by reuse and time consumption was reduced to 1/20 of the pathology *** addition,it is flexible to set samples and easy to realize automatic operation due to the great polarization-insensitivity of the proposed biosensor,which can further reduce labor costs in the *** is envisioned that the proposed biosensor will present immense potential in the fields of cancer detection,distinguishing different cancers,identifying primary lesion cancer or metastatic cancer.

关键词： terahertz metasurface biosensor cancer detection

Transitions between mesenchymal and epithelial states and the concomitant gene expression changes

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science Foundation in China 2016年第1期24卷 50-62页

作者： LIANG LiNing sun Hao LI LingYu ZHENG hui CAS Key Laboratory of Regenerative Biology Guangdong Provincial Key Laboratory of Stem Cell and Regenerative MedicineGuangzhou Institutes of Biomedicine and HealthChinese Academy of Sciences Anhui University

Epithelial-mesenchymal transition(EMT),mesenchymal-epithelial transition(MET),and even the sequential EMT-MET can be observed during multiple cell fate conversions including cancer progression and embryonic *** the current review,we first focused on the existence and beneficial roles of the sequential EMT-MET during three typical cell fate conversions,differentiation from pluripotent stem cells(PSCs)to neurons,de-differentiation from mouse embryonic fibroblasts(MEFs)to PSCs,and trans-differentiation from MEFs to *** tried to provide some preliminary hypotheses to connect EMT-MET and cell fate conversions,like the possible contributions of the intermediate mesenchymal state to iPSCs generation and *** intermediate mesenchymal state during sequential EMT-MET was further discussed by exploring the conserved signatures on gene expression during a variety of *** on the interaction among vitamin C,DNA methylation,and EMT/MET was also provided.

关键词： Epithelial-mesenchymal transition Cell fate conversions Reprogramming Trans-differentiation

A euryarchaeal histone modulates strand displacement synthesis by replicative DNA polymerases

在线全文

学校读者我要写书评

暂无评论

Science China(Life Sciences) 2016年第7期59卷 709-716页

作者： Fei sun Li Huang State Key Laboratory of Microbial Resources Institute of Microbiology Chinese Academy of Sciences

Euryarchaeota and Crenarchaeota, the two main lineages of the domain Archaea, encode different chromatin proteins and differ in the use of replicative DNA polymerases. Crenarchaea possess a single family B DNA polymerase(Pol B), which is capable of strand displacement modulated by the chromatin proteins Cren7 and Sul7 d. Euryarchaea have two distinct replicative DNA polymerases, PolB and PolD, a family D DNA polymerase. Here we characterized the strand displacement activities of Pol B and Pol D from the hyperthermophilic euryarchaeon Pyrococcus furiosus and investigated the influence of HPf A1, a homolog of eukaryotic histones from P. furiosus, on these activities. We showed that both Pol B and Pol D were efficient in strand displacement. HPf A1 inhibited DNA strand displacement by both DNA polymerases but exhibited little effect on the displacement of a RNA strand annealed to single-stranded template DNA. This is consistent with the finding that HPf A1 bound more tightly to double-stranded DNA than to a RNA:DNA hybrid. Our results suggest that, although crenarchaea and euryarchaea differ in chromosomal packaging, they share similar mechanisms in modulating strand displacement by DNA polymerases during lagging strand DNA synthesis.

关键词： euryarchaea PolB PolD strand displacement archaeal histone

Clinical significance of skip lymph-node metastasis in pN1 gastric-cancer patients after curative surgery

在线全文

学校读者我要写书评

暂无评论

Gastroenterology Report 2019年第3期7卷 193-198,I0002页

作者： Jin-Yuan Liu Jing-Yu deng Nan-Nan Zhang hui-Fang Liu Wei-Lin sun Wen-Ting He Yan Wang Li Zhang Han Liang department of Gastroenterology Tianjin Medical University Cancer HospitalCity Key Laboratory of Tianjin Cancer Center and National Clinical Research Center for CancerTianjinP.R.China department of General Surgery The Affiliated Hospital of Nankai UniversityTianjinP.R.China

Background:In addition to the stepwise manner of lymph-node metastasis from the primary tumour,the skip lymph-node metastasis(SLNM)was identified as a low-incidence metastasis of gastric cancer(GC).So far,both the mechanism and outcome of SLNM have not been elucidated *** purpose of this study was to analyse the clinical significance and the potential mechanism of SLNM in GC patients who had lymph-node ***:Clinicopathological data and follow-up information of 505 GC patients who had lymph-node metastasis were analysed to demonstrate the significance of SLNM in evaluating the prognostic *** to the pathological results,all GC patients who had lymph-node metastasis were categorized into three groups:patients with the perigastric lymphnode metastasis,patients with the perigastric and extragastric lymph-node metastasis and patients with ***:Among the 505 GC patients who had lymph-node metastasis,24(4.8%)had pathologically identified *** location of lymph-node metastasis was not significantly associated with 5-year survival rate and overall survival(OS)(P=0.194).The stratified survival analysis results showed that the status of SLNM was significantly associated with the OS in patients with pN1 GC(P=0.001).The median OS was significantly shorter in 19 pN1 GC patients with SLNM than in 100 patients with perigastric lymph-node metastasis(Pdergoing curative *** the 19 pN1 GC patients with SLNM,17(89.5%)had metastatic lymph nodes along the common hepatic artery,around the celiac artery or in the hepatoduodenal ***:SLNM may be considered a potentially practicable indicator for prognosis among various subgroups of pN1 GC patients.

关键词： Stomach neoplasm metastasis prognosis multivariate analysis

Phosphorus in the aerosols over oceans transported offshore from China to the Arctic Ocean: Speciation, spatial distribution, and potential sources

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Advances in Polar Science 2015年第3期26卷 232-238页

作者： sun Chen XIE Zhouqing KANG hui YU Juan Institute of Polar Environment School of Earth and Space Sciences University of Science and Technology of China

Atmospheric aerosol samples were collected from July to September 2008 onboard a round-trip cruise over the Eastern China Sea, Japan Sea, Western North Pacific Ocean, and the Arctic Ocean （31.1°N-85.18°N, 122.48°E-146.18°W）. Total phosphorus （TP） and total inorganic phosphorus （TIP） were analyzed. The organic phosphorus （OP） was calculated by subtracting TIP from TP. Average concentrations of TP in the East Asia, Western North Pacific and Arctic Ocean were 7.90±6.45, 6.87±6.66 and 7.13±6.76 ng.m^3, while TIP levels were 6.67±5.02, 6.07±6.58, and 6.23±5.96 along the three regions. TP and TIP levels varied considerably both spatially and temporally over the study extent. TIP was found to be the dominant species in most samples, accounting for 86.6% of TP on average. OP was also a significant fraction of TP due to the primary biogenic aerosol （PBA） contribution. The phosphorus in the atmospheric aerosol over the Arctic Ocean had a higher concentration than previous model simulations. Source apportionment analysis indicates that dust is an important phosphorus source which can be globally transported, and thus dust aerosol may be an important nutrient source in some remote regions.

关键词： phosphorus aerosol spatial distribution speciation sources Arctic Ocean

Genetic and genomic analyses for economically important traits and their applications in molecular breeding of cultured fish

在线全文

学校读者我要写书评

暂无评论

Science China(Life Sciences) 2015年第2期58卷 178-186页

作者： TONG JinGou sun XiaoWen State Key Laboratory of Freshwater Ecology and Biotechnology Institute of Hydrobiology Chinese Academy of Sciences Heilongjiang Fisheries Research Institute Chinese Academy of Fishery Sciences

The traits of cultured fish must continually be genetically improved to supply high-quality animal protein for human *** important fish traits are controlled by multiple gene quantitative trait loci(QTL),most of which have minor effects,but a few genes may have major effects useful for molecular *** this review,we chose relevant studies on some of the most intensively cultured fish and concisely summarize progress on identifying and verifying QTLs for such traits as growth,disease and stress resistance and sex in recent *** potential applications of these major-effect genes and their associated markers in marker-assisted selection and molecular breeding,as well as future research directions are also *** genetic and genomic analyses will be valuable for elucidating the mechanisms modulating economically important traits and to establish more effective molecular breeding techniques in fish.

关键词： aquaculture fish economic traits QTL major genes molecular markers molecular breeding