低压无极灯汞蒸气压控制

汞蒸气压控制是无极灯的关键技术之一 ,通过对纯汞和汞齐的性能进行分析 ,指出汞齐的成分配比、用量和安放位置的确定是控制汞蒸气压达到最佳值的有效途径 .     

An in vitro evaluation of novel NHA/zircon plasma coating on 316L stainless steel dental implant

The surface characteristics of an implant that influence the speed and strength of osseointegration include crystal structure and bioactivity. The aim of this study was to evaluate the bioactivity of a novel natural hydroxyapatite/zircon(NHA/zircon) nanobiocomposite coating on 316L stainless steel(SS) dental implants soaking in simulated body fluid. A novel NHA/zircon nanobiocomposite was fabricated with 0(control),5, 10, and 15 wt% of zircon in NHA using ball mill for 1 h. The composite mixture was coated on SS implants using a plasma spray method.Scanning electron microscopy(SEM) was used to evaluate surface morphology, and X-ray diffraction(XRD) was used to analyze phase composition and crystallinity(Xc). Further, calcium ion release was measured to evaluate the coated nanobiocomposite samples. The prepared NHA/zircon coating had a nanoscale morphological structure with a mean crystallite size of 30–40 nm in diameter and a bone-like composition,which is similar to that of the biological apatite of a bone. For the prepared NHA powder, high bioactivity was observed owing to the formation of apatite crystals on its surface. Both minimum crystallinity(Xc=41.1%) and maximum bioactivity occurred in the sample containing 10 wt% of zircon because of minimum Xcand maximum biodegradation of the coating sample.     

Effects of different types of palatal lateral excisions on growth and development of maxilla and dental arch

Objective： This study aimed to explore the effects of different types of palatal lateral excisions on the growth and development of the maxilla and dental arch, and to investigate the underlying mechanisms. Methods： A total of 112 3-week-old Sprague-Dawley （SD） male rats were randomly divided into a control and 3 experimental groups： the mucoperiosteal denudation group, the mucosal flap excision group, and the periosteum excision group. In the experimental groups, bilateral mucoperiosteal, mucosal flap and periosteum were excised respectively in the lateral one half of the palate. Four rats in each group were randomly chosen for sacrifice every two weeks. The maxilla was dissected following the excision. The widths of the maxilla and dental arch were measured and the histological phenomena were investigated at different phases. At the same time, 12 animals in each group were sequentially injected with calcein every two weeks. Three animals in each group, whose fluorescent labeling was used, were sacrificed for investigating bone formation at Week 8 following injection. Results： （1） Each experimental group presented the constriction of the maxilla and dental arch. The upper first molars in the experimental groups inclined medially. The mucoperiosteal denudation group showed the largest degree of effect followed by the periosteum excision group. The indices of the mucosal flap excision group, which retained the structures of the periosteum layer, had the most approximate values to the control group; （2） Different histological changes among the experimental groups were detected. The fibers penetrated into the palatal bone as Sharpey＇s fibers in the mucoperiosteal denudation group. The pattern of bone deposition was the bundle type. Sharpey＇s fibers were not found in the mucosal flap and periosteum excision groups and the depositions of palatal bone were the lamellar type as those in the control group; （3） The rates of bone deposition in the experimental groups decreased compared with the     

Novel Ag nanocrystals based dental resin composites with enhanced mechanical and antibac terial propert ies

The aim of this work was to investigate the effect of trace addition of oleic acid coated Ag nanocrystals(Ag NCs) on mechanical and antibacterial properties of dental resin composites.Composites(70 wt%of silica loading) with 25 ppm,50 ppm,75 ppm and 100 ppm(wt) Ag NCs were prepared and the composite without Ag NCs served as a control.The experimental results showed that the addition of Ag NCs significantly improved the strength and modulus of the resin composite without compromising the shade.For the composite with 50 ppm Ag NCs,fiexural strength(140.3 MPa),modulus(13.2 GPa)and compressive strength(347.2 MPa) were increased by 4.1%,22.2%,13.3%,respectively,compared with the control.The antibacterial test demonstrated that trace Ag NCs provided the resin composites with an antibacterial effect.Such strong and antibacterial dental resin composites might be advantageous to prevent secondary caries and be potential for future clinical applications.     

小波框架的齐次逼近性质

文章先给出了两个Banach空间,它们中的函数对于满足一定条件的参数序列能产生小波框架,并且在参数和生成元函数有微小扰动的情况下仍然为小波框架。后在前文的基础上放宽了函数属于F1(R)的充分条件。一步,F0(R)中的生成元产生的小波框架满足强齐次逼近条件,也就是函数的小波框架展开式的逼近率在它进行伸缩平移以后是不变的。     

Na｜β－Al＿2O＿3｜Na＿xHg＿（1－x）（液态）电池电动势的测量和计算

应用Ｎａ｜β－Ａｌ＿２Ｏ＿３｜Ｈｇ固体电解质电池，制备了６８个钠汞齐Ｎａ＿ｘＨｇ＿（１－ｘ）（ｘ：０．０３５～０．８８４６）组分．从Ｎａ／Ｎａ＿ｘＨｇ＿（１－ｘ）电池电动势的测量，测定了Ｎａ＿ｘＨｇ＿（１－ｘ）的熔点和在熔化过程电池反应中的熵变和焓变．实验得出Ｎａ／Ｎａ＿ｘＨｇ＿（１－ｘ）（液态）电池电动势Ｅ和汞齐中的钠摩尔分数ｘ存在Ｅ＝α（－ｌｇｘ）￣ｂ的关系式．线性方程式ｌｇＥ＝ｌｇα＋ｂｌｇ（－ｌｇｘ）中的ｌｇα和ｂ在各个组分ｘ（０．０６５～０．１６，０．１６～０．３３３，０．３３３～０．７１５）和温度范围内分别是温度的线性函数．相应于ｘ≥０．７１５时的ｌｇα和ｂ值（１００≤ｔ≤３５０℃）为ｌｇα＝－０．１７８８－１．０１０×１０￣（－３）ｔ＋１．１０９×１０￣（－６）ｔ￣２，ｂ＝１．７８３－１．７１３×１０￣（－３）ｔ＋１．４７５×１０￣（－６）ｔ￣２     

120名老年人牙体病调查分析

对120名老年人牙体病进行调查.受检者中,有105名患者有牙龋坏,龋坏率为87.7%.平均龋坏数为每人3.5个.有81名患者牙齿有缺失,缺失牙数为383个.龋病、缺失牙仍是老年人的主要口腔疾患,其患病率随年龄递增,治疗率明显下降.     

生物活性羟基磷灰石牙膏的研制

本文论述了羟基磷灰石及由其所得的生物活性牙膏的制备方法，并对这种牙膏防治牙病和保健牙齿的机理进行了全面探讨。结果表明：生物活性羟基磷灰石牙膏具有任何药物牙膏所无法比拟的独特功效和作用，应用前景广阔。     

Bochner-Riesz算子及其交换子在加权(L_ω~q,L~p)~α(R~n)空间上的有界性

利用Ap权性质及分析中的不等式,得到Bochner-Riesz算子Tn-12R及由BMO(Rn)函数b(x)和TδR(δ≥(n-1/2))生成的交换子在加权共合空间(Lqω,Lp)α(Rn)上的有界性,其中1q≤αp≤∞.     

牙周一牙髓联合病变治疗的临床观察

目的：观察派丽奥软膏、甲硝唑棒、3％碘伏液治疗牙周牙髓联合病变的疗效。方法：对90颗牙周一牙髓联合病变的磨牙分派丽奥软膏、甲哨唑棒3％碘伏液三组进行治疗，观察2W，进行记录。结果：派丽奥组治疗成功率100％，甲硝唑棒组86．7％，3％碘伏组66．7％。结论：派丽奥组牙周治疗疗效显，是一种新型牙周缓释剂。