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Pollination characteristics of the ephemeroid plant Eremurus anisopterus

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Frontiers in Biology 2008年第3期3卷 315-319页

作者： miao ma Junfeng FAN Jing LI The Key Oasis Eco-Agriculture Laboratory of Xinjiang Production and Construction Group Shihezi UniversityShihezi 832003China College of Life Science Shihezi UniversityShihezi 832003China

This study was conducted to examine the pol-lination characteristics of Eremurus anisopterus,an ephe-meroid plant in the Gurbantunggut Desert in Xinjiang,*** integrative approach combining field studies with lab analysis was *** traps were used to measure air-borne pollen loads and artificial isolation experiments were applied to test the potentiality of cross-pollination or *** show that the duration of the flowering of Eremurus anisopterus varied from late April to *** of a single flower often lasted for 1 ***,if the daily maximum air temperature was under 20℃,the anthesis of a single flower could be prolonged up to 2 *** pollen dispersion period of the single flower could last for 4 to 5 h,from 10:30 to 15:00 local time,with the duration of pollen dispersion for a single anther lasting approximately 40 *** heterotypical maturation of the stigma could significantly prolong the pollen dispersion period of the single flower suggesting an adaptation to the habitat of *** in the desert where the pollinators were not *** timing of the blossoms of the ephemeroid plant show close correlations with the wind velocity and the habit and characteristics of the pollinators in the *** pollens may be spread to over 70 m by wind with approximately 60%of the pollens falling within 20 m away from the ***,especially bees,hover flies,flesh flies,mason bees and Halictus *** very important *** and hover flies usually landed on the yellowish green spot on the tepal and then entered the flower along the purple vein on the pink *** yellowish green spot might be a mimetic structure of nectar that could attract insects to *** was also an adaptation of the plant to the sandy desert environment.A higher visiting frequency was reached between 10:30 and 13:*** pollen-ovule ratio(P/O)of ***(6164)suggested that the species was from cross-pollination according to

关键词： ephemeroid plant Eremurus anisopterus pollination heterotypical maturation of stamina P/O

Analytical study on water hammer pressure in pressurized conduits with a throttled surge chamber for slow closure

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Water Science and Engineering 2010年第2期3卷 174-189页

作者： Yong-liang ZHANG Ming-fei miao Ji-ming ma State Key Laboratory of Hydroscience and Hydraulic Engineering Department of Hydraulic Engineering Tsinghua University Beijing 100084 P. R. China

This paper presents an analytical investigation of water hammer in a hydraulic pressurized pipe system with a throttled surge chamber located at the junction between a tunnel and a penstock, and a valve positioned at the downstream end of the penstock. Analytical formulas of maximum water hammer pressures at the downstream end of the tunnel and the valve were derived for a system subjected to linear and slow valve closure. The analytical results were then compared with numerical ones obtained using the method of characteristics. There is agreement between them. The formulas can be applied to estimating water hammer pressure at the valve and transmission of water hammer pressure through the surge chamber at the junction for a hydraulic pipe system with a surge chamber.

关键词： throttled surge chamber water hammer orifice analytical formula

Novel single-walled carbon nanotubes periodically embedded with four- and eight-membered rings

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Frontiers of physics 2018年第4期13卷 175-184页

作者： Xiao-Ning Wang Jun-Zhe Lu Heng-Jiang Zhu Fang-Fang Li miao-miao ma Gui-Ping Tan College of Physics and Electronic Engineering Xinjiang Normal University Urumqi 830055 China Key Laboratory of Mineral Luminescence materials and Microstructures of Xinjiang Uygur Autonomous Region Urumqi 830054 China

Based on experimental results, we obtain five types of single-walled carbon nanotube （SWNT） clusters with different chirality indices and diameters using density functional theory （DFT）. We then obtain the corresponding SWNTs by using periodic boundary conditions. Studies of the stability and elec- tronic properties show that the stability of the novel SWNTs is independent of the chirality index and relates only to the tube diameter; larger diameters correspond to more stable SWNTs. The electronic properties all show metallic characteristics independent of the chirality indices and tube diameters, thereby promoting the application of metallic-type SWNTs.

关键词： four- and eight-membered rings novel SWNTs stability electronic properties

Factors influencing oil recovery by surfactant-polymer flooding in conglomerate reservoirs and its quantitative calculation method

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Petroleum Science 2022年第3期19卷 1198-1210页

作者： Feng-Qi Tan Chun-miao ma Jian-Hua Qin Xian-Kun Li Wen-Tao Liu College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing100049China Key Laboratory Computational Geodynamics Chinese Academy of SciencesBeijing100049China Xinjiang Oilfield Company PetroChinaKaramayXinjiang834000China

This study aims to clarify the factors influencing oil recovery of surfactant-polymer(SP)flooding and to establish a quantitative calculation model of oil recovery during different displacement stages from water flooding to SP *** conglomerate reservoir of the Badaowan Formation in the seventh block of the Karamay Oilfield is selected as the research object to reveal the start-up mechanism of residual oil and determine the controlling factors of oil recovery through SP flooding experiments of natural cores and microetching *** experimental results are used to identify four types of residual oil after water flooding in this conglomerate reservoir with a complex pore structure:oil droplets retained in pore throats by capillary forces,oil cluster trapped at the junction of pores and throats,oil film on the rock surface,isolated oil in dead-ends of flow *** the four types of residual oil identified,the SP solution can enhance oil recovery by enlarging the sweep volume and improving the oil displacement ***,the viscosity-increasing effect of the polymer can effectively reduce the permeability of the displacement liquid phase,change the oil-water mobility ratio,and increase the water ***,the stronger the shear drag force of the SP solution,the more the crude oil in a porous medium is ***,the surfactant can change the rock wettability and reduce the absorption capacity of residual oil by lowering interfacial *** the same time,the emulsification further increases the viscosity of the SP solution,and the residual oil is recovered effectively under the combined effect of the above two *** the four start-up mechanisms of residual oil identified after water flooding,enlarging the sweep volume and improving the oil displacement efficiency are interdependent,but their contribution to enhanced oil recovery are *** SP flooding system primarily enlarges the sweep volume by increasing viscos

关键词： Conglomerate reservoir Water flooding Surfactant-polymer flooding Residual oil type Influencing factor Enhanced oil recovery Computational model

Recent advances in Pt catalysts and membrane electrode assemblies fabrication for proton exchange membrane fuel cells

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Rare Metals 2024年第9期43卷 4198-4221页

作者： miao ma Li-Xiao Shen Jing Liu Bin Xu Yun-Long Zhang Lei Zhao Zhen-Bo Wang School of Chemistry and Chemical Engineering Harbin Institute of TechnologyHarbin 150001China College of Environmental and Chemical Engineering Yanshan UniversityQinhuangdao 066004China Unipower Hydrogen Technology(Jiangsu)Corporation Changzhou 213176China

Proton exchange membrane fuel cells(PEMFCs)have been identified as a highly promising means of achieving sustainable energy conversion.A crucial factor in enhancing the performance of PEMFCs for further potential energy applications is the advancement in the field of catalyst engineering that has led to remarkable performance enhancement in facilitating the oxygen reduction reaction(ORR).Subsequently,it is important to acknowledge that the techniques used in preparation of membrane electrode assemblies(MEAs),the vital constituents of PEMFCs,also possess direct and critical influence on exhibiting the full catalytic activity of meticulously crafted ***,a succinct summary of the most recent advancements in Pt catalysts for ORR was offered and their underly catalytic mechanism were ***,both laboratory-scale and industrial-scale MEA fabrication techniques of Pt catalysts were ***,a detailed analysis of the connections between materials,process,and performance in MEA fabrication was presented in order to facilitate the development of optimal catalyst layers.

关键词： Pt catalysts Oxygen reduction reaction Membrane electrode assemblies MEA fabrication techniques

Hydrophobic surface modification of chitosan gels by stearyl for improving the activity of immobilized lipase

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Chinese Chemical Letters 2009年第8期20卷 995-999页

作者： Hong Tao Deng Juan Juan Wang miao ma Zhong Yang Liu Fei Zheng College of Chemistry Central China Normal University Wuhan 430079 China

The hydrophobic surface modification of chitosan gels was carried out using the amidating reaction of amido groups on a gel surface with stearic acid activated by 1-ethyl-3-（3-dimethylaminopropyl）-carbodiimide hydrochloride （EDC） and N-hydroxysuccinimide （NHS）. Lipases from Candida rugosa were adsorbed on the nascent chitosan gels （CS） and stearyl-modified gels （SCS） with different degrees of amidation. The increased surface hydrophobicity of chitosan gels improved the adsorption capacity and activity of the immobilized lipase. SCS with 31.46% amidation showed the maximum activity retention （83.43%）. The experimental results suggest that the moderate surface hydrophilicity/hydrophobicity of chitosan gels is necessary for the improvement of the activity of immobilized lipase. ？2009 Hong Tao Deng. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Lipase Chitosan Surface modification Adsorption

Protein expression trends of DNMT1 in gastrointestinal diseases:From benign to precancerous lesions to cancer

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World Journal of Gastrointestinal Oncology 2019年第12期11卷 1141-1150页

作者： Tian-miao ma Li-Ping Sun Nan-Nan Dong Ming-Jun Sun Yuan Yuan Department of Gastroenterology the First Hospital of China Medical UniversityShenyang 110001Liaoning ProvinceChina Tumor Etiology and Screening Department of Cancer Institute and General Surgery the First Hospital of China Medical UniversityShenyang 110001Liaoning ProvinceChina

BACKGROUND In recent years,the incidence of gastrointestinal(GI)cancer in China has increased *** detection and appropriate therapy are considered to be the key to treat GI ***1 takes an active part in the advancement of GI cancer,which will change as the disease *** its expression characteristics in the dynamic variations of GI carcinogenesis are still *** To investigate the expression characteristics of DNMT1 in different GI *** We detected the expression of DNMT1 in 650 cases of different GI diseases by immunohistochemistry,including 90 cases of chronic superficial gastritis(CSG),72 cases of atrophic gastritis with intestinal metaplasia(AG/GIM),54 cases of low-grade intraepithelial neoplasia(GLIN),66 cases of high-grade intraepithelial neoplasia(GHIN),71 cases of early gastric cancer(EGC),90 cases of normal intestinal mucosa(NIM),54 cases of intestinal low-grade intraepithelial neoplasia(ILIN),71 cases of intestinal high-grade intraepithelial neoplasia(IHIN),and 82 cases of early colorectal cancer(ECRC).RESULTS In the CSG group,all cases showed weakly positive or negative expression of ***,in other four groups(AG/GIM,GLIN,GHIN,and EGC),the positive expression rate gradually increased with the severity of the diseases;the negative or weakly positive cases accounted for 55.56%(40/72),38.89%(21/54),1.52%(1/66),and 1.41%(1/71),***,the moderately positive cases were 44.44%(32/72),57.41%(31/54),80.30%(53/66),and 43.66%(31/71),*** strongly positive cases only existed in the GLIN(3.70%,2/54),GHIN(18.18%,12/66),and EGC(54.93%,39/71)*** differences between any two groups were statistically significant(P<0.05).Similarly,in the NIM group,cases with weakly positive expression of DNMT1 were predominant(91.11%,82/90),and the rest were moderately positive cases(8.89%,8/90).In the ILIN,IHIN,and ECRC groups,the rates of cases with weak or negative expression of DNMT1 were 46.30%(25/54

关键词： Gastric cancer Colorectal cancer DNMT1 Precancerous lesion Intraepithelial neoplasia

Effect of continuous nursing combined with respiratory exercise nursing on pulmonary function of postoperative patients with lung cancer

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World Journal of Clinical Cases 2023年第6期11卷 1330-1340页

作者： Qiong-Xiang Qiu Wen-Juan Li Xi-miao ma Xue-Hua Feng Department of Thoracic Surgery Haikou People’s HospitalHaikou Affiliated Hospital of Central South University Xiangya School of MedicineHaikou 570208Hainan ProvinceChina

BACKGROUND Lung cancer is a malignant tumor with high morbidity and mortality among *** is currently one of the primary methods of treating lung *** it can slow down the progression of the disease by removing the lesion,this invasive surgery inevitably damages the integrity of the patient’s ***,the patient’s pulmonary function may have a low compensatory capacity after surgery,causing various respiratory diseases such as atelectasis,respiratory function decline,and even serious cardiovascular *** of these have great negative impacts on the surgical effect and the prognosis of *** the continuous exploration and development of nursing,continuous nursing and respiratory exercise nursing have been gradually applied in the nursing of patients after lung cancer surgery,and have achieved good nursing *** To investigate the effect of continuous nursing combined with respiratory exercise nursing on the pulmonary function of postoperative patients with lung *** A total of 80 patients with lung cancer who underwent surgery in our hospital from January 2021 to December 2021 were selected as the study *** subjects were randomly divided into the control group(n=40 cases)and the experimental group(n=40 cases).Patients with lung cancer in the control group were given conventional nursing after surgery,while the experimental group was given continuous nursing combined with respiratory exercise nursing based on conventional *** recovery of pulmonary function and respiratory symptoms was observed before and after 3 mo of intervention in both *** pulmonary function parameters,blood gas analysis,MD Anderson Symptom Inventory-lung cancer module(MDASI-LC)scores,incidence of pulmonary complications,and Morisky compliance scores were compared between the two groups before and after 3 mo of *** There was no significant difference in pulmonary function and blood gas analysis betwee

关键词： Postoperative lung cancer Continuous nursing Respiratory exercise nursing Pulmonary function

Recent advances in high-loading catalysts for low-temperature fuel cells: From nanoparticle to single atom

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Susmat 2021年第4期1卷 569-592页

作者： Lixiao Shen miao ma Fengdi Tu Zigang Zhao Yunfei Xia Kokswee Goh Lei Zhao Zhenbo Wang Guangjie Shao College of Environment and Chemical Engineering State Key Laboratory of Metastable Materials Science and TechnologyHebei Key Laboratory of Heavy Metal Deep-Remediation in Water and Resource ReuseYanshan UniversityQinhuangdaoP.R.China MIIT Key Laboratory of Critical materials Technology for New Energy Conversion and Storage State Key Lab of Urban Water Resource and EnvironmentSchool of Chemistry and Chemical EngineeringHarbin Institute of TechnologyHarbinP.R.China

Low-temperature fuel cells(LTFCs)are considered to be one of the most promising power sources for widespread application in sustainable and renew-able energy conversion *** remarkable advances have been made in the mass activity of catalysts,mass transport impedance needs to be urgently addressed at a well-designed membrane electrode assembly(MEA)*** the loading of electrocatalysts is conducive to prepare thinner and more efficient MEAs owing to the resulting enhanced reactant permeability,better proton diffusion,and lower electrical ***,recent progress in high-loading(≥40 wt.%)Pt nanoparticle catalysts(NPCs)and high-loading(≥2 wt.%)single-atom catalysts(SACs)for LTFC applications are reviewed.A summary of various synthetic approaches and support materials for high-loading Pt NPCs and SACs is systematically *** influences of high surface area and appropriate surface functionalization for Pt NPCs,as well as coordina-tion environment,spatial confinement effect,and strong metal-support interac-tions(SMSI)for SACs are ***,this review presents some ideas regarding challenges and future opportunities of high-loading catalysts in the application of LTFCs.

关键词： high-loading catalysts low-temperature fuel cells membrane electrode assembly nanoparticle catalysts single-atom catalysts