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111.
ElectrochrondcmaterialshavebeenattractingmoreandmoreattentionbecauseoftheirusefulnessonSmartWindows'.Byharnessingthesolarradiationtobuildingsorautomobileinteriors,onecanmodifytheilluminationandheatgainedandconvertitintoenergytoimprovecomfort,bytakingadvantageofthelowpowerrequirementSofelectrochromicmaterials.Amongthesematerials,Nio.H,isthemostpromisingduetoitShighcoloringefficiency,lowmaterialcost,highstability,andinparticular,its"grayeffectlll'2.Inaddition,Nio.H,isalsousedwidelyasapositive…  相似文献   
112.
本文解析了同位素标记的63Cu-14N-HAP,65Cu-14N-HAP,63Cu-15N-HAP。65Cu-15N-HAP,和Cu-15N-HAP,等五种配合物在四氢呋喃中,在77K温度下测得的分辨较好的ESR波谱。从图上不仅得到了63Cu和63Cu的超精细分裂,而且还得出分辨较好的14N和15N的超超精细分裂。比较合理地确定了gx,gy,gz;Ax65,Ay65,Az65和Ax63,Ay63,Az63以及A15,A15和A14,A14等张量参数。利用测得的波谱参数计算了键参数,并讨论了配合物的电子结构及成键特性,得到了较满意的结果。  相似文献   
113.
Mercaptopropyltrimethoxysilane (MPTS) bearing mercapto groups was used to form self-assembly monolayers (SAMs) on glass substrates by solution extraction.SEM,XRD and rubbing test analysis illustrated that the Ag film on the SAMs-modified glass was more durable than that on the commonly-modified glass and that the crystallinity of Ag film on the SAMs-modified glass was identical with those of the Ag film on the commonly-modified glass and pure Ag.  相似文献   
114.
硒(Ⅳ)—碘酸钾体系极谱法测定痕量亚硫酸根   总被引:2,自引:1,他引:2  
李建平  舒柏崇 《分析化学》1997,25(7):792-795
报道了一种单扫描极谱测定痕量亚硫酸根的方法。在高氯酸介质中,亚硫酸根可将Se(Ⅳ)还原为Se(0),在PH10.5的NH3-NH4Cl缓冲溶液中,在碘酸钾存在下,于-0.90V(vs.SCE)处产生一个灵敏的还原催化波,导数波高与亚硫酸根浓度在0-0.4mg/L范围内有线性关系,检出限为2μg/L。  相似文献   
115.
Fabrication of polyurethane molecular stamps (PU stamps) based on polypropylene glycol (PPG) and toluene dissocyanate (TDI), using 3,3′-dichloro-4,4′-methylenedianiline (MOCA) as the crosslinker ,is reported. It was shown from the contact angle measurement that PU stamps surface has good affinity with acetonitrile,guaranteeing the well distribution of DNA monomers on patterned stamps. Laser confocal fluorescence microscopy images of oligonucleotide arrays after hybridization confirmed polyurethane is an excellent material for molecular stamps when ransferring polar chemicals and conducting rections on interfaces by stamping.  相似文献   
116.
lntroductionMethanolissynthesizedbyblendgasofCOandH2.FeedstockgasformethanolsynthesismustbeinlinewiththefollowingstoichiometricrelationtR=(H2-Co2)/(Co CO2)52Inaddition,thecontentofCo2shouldbelowerthan8%ll1.MethanereformingwithsteamandCO2canproducethequalifiedsynthesisgasformethanolsynthesisinindustry.ComParedwithtndtionalsteaInrefotheng,thefeedstocksynthsisgasproducedbymethanreformingwithsteamandCO2docsnotneedseparaingandcanbedirectlyusedinmethanolsynthesis.Therefore,thecostofmethanolca…  相似文献   
117.
IsodonleucoPhyll(Dunn)Hara(Labiatae),distributedinthenorthwestareaofYunnanProvince,isusedasfolkmedicineforitsantibacterialandanti-inflanimatoryactivitybylocalpractitioners'.Fromtheleavesofthisplant,fournewent-kauranetypediterPenoids,baiyecrystalA'C1'3andePi-baiyecrystalC4,wereisolated.Thispaperpresentstheirsimctureelucidation.BaiyecrystalA1C26H34O1owasdeterminedbyHRMS(5O6.2157,calc5o6.2l52).Itsmassspectrumshowedthatthemolecularion(wt5O6)was58amumorethanthatofeffusaninD5',aknownkaureno…  相似文献   
118.
Nanoporous materials have been widely applied to biosensor investigation. Recently, Guo et al. have investigated the mesoporous materials modified carbon paste electrode for rapid cTnI (cardiac troponin I) detection with enhanced sensitivity1-3. However, …  相似文献   
119.
First-class course construction is the foundation of first-class undergraduate education construction. Based on the understanding of the "Two properties and one degree" standard of first-class course, key characteristics of the first-class course construction are summarized as accurate positioning, clear teaching goals, good construction foundation, advanced pedagogy, first-class construction, remarkable effectiveness and preferential demonstration. Taking the construction of first-class physical chemistry course in Shandong University as an example, the course orientation, the determination of teaching objectives and the design and implementation of the teaching are introduced. The practice and experience of the course construction are demonstrated in five aspects as first-class foundation, first-class teachers, first-class resources, first-class pedagogical ideas and first-class achievements. It can be used as the reference for the future construction of first-class courses in other universities.  相似文献   
120.
Eight new tetramic acid derivatives, cladosporiumins A–H (18) were isolated from a culture broth of Cladosporium sp. SCSIO z0025 derived from the deep-sea sediment collected from Okinawa Trough. Their structures were elucidated by extensive spectroscopic data analysis. Compounds 13 were unique 3-acyltetramic acids with a hexyl enic alcohol side chain and a six-membered lactone ring substituted at C-3 of the 2, 4-pyrrolidinedione skeleton. The absolute configurations of chiral carbons of the 2, 4-pyrrolidinedione unit in 14 and 7 were established by quantum chemical calculations of the electronic circular dichroism (ECD) spectra. And the absolute configurations of chiral carbons of the six-membered lactone ring in 13 were established by density functional theory calculation of their 13C NMR chemical shifts. In addition, all the compounds were tested for cytotoxic, antibacterial, anti-biofilm, and AchE inhibitory activities.  相似文献   
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