阿拉伯胶防止镍阴极长粒子的机理

本文研究了镍阴极长粒子的原因、抑制粒子长大的方法,详细研究了阿拉伯胶防止镍阴极长粒子的机理。

阴极铜酥脆和长粒子原因探讨及工艺改进

概述了沈阳冶炼厂技改前阴极铜的质量状况，分析了阴极铜酥脆和长粒子的原因，介绍了技改措施及技改后的效果。

镓酸锌基长余辉纳米粒子的研究及应用进展

长余辉发光纳米粒子(PLNPs)具有优异的光学性质,在生物医学领域受到广泛关注。随着科学技术的发展,PLNPs基质材料从硫化物基质发展到铝酸盐基质、硅酸盐基质以及极具发展潜力的镓酸锌(ZGO)基质。ZGO基PLNPs具有三维尖晶石结构,其大量的反位缺陷、较宽的带隙差、超长的近红外余辉发射能够消除生物组织的自体荧光干扰,被广泛应用于生物检测、诊疗一体化及生物成像等领域。综述了不同基质PLNPs的研究进展,介绍了ZGO基PLNPs在生物检测、成像以及诊疗一体化中的应用,并对未来ZGO基PLNPs的发展趋势进行了展望。

长程α粒子探测器研究进展

α粒子射程短,常规α放射性活度直接测量方法难以测量不规则表面及管道内等区域的α放射性活度。长程α粒子探测器(long-rangeαdetector,LRAD)是目前用于此类区域α放射性污染的有效测量手段之一,被广泛应用于坑洞、核设施管道内等难以近距离测量环境的α放射性活度监测。本文介绍了LRAD的基本原理、发展及现状,并展望了LRAD的应用前景及发展方向。

长余辉发光粒子与光催化剂在SiC晶圆化学机械抛光中的协同作用

目的获得一种可改善单晶SiC晶圆化学机械抛光(CMP)效率的复合增效技术,实现单晶SiC晶圆高效率和低成本的加工要求,并对其增效机理进行深入研究。方法通过抛光实验和原子力显微镜测试,探究长余辉发光粒子(LPPs)与不同光催化剂的协同作用对SiC-CMP的材料去除速率和表面粗糙度的影响。结合扫描电子显微镜(SEM)、紫外-可见漫反射光谱仪(UV-vis)、光致发光光谱仪(PL)和X射线光电子能谱仪(XPS)等仪器的测试结果,研究LPPs与光催化剂的协同增效机理。结果与传统CMP的条件相比,在光催化条件下采用LPPs(质量分数0.5%)+TiO_(2)(质量分数0.5%)+H_(2)O_(2)(质量分数1.5%)+Al_(2)O_(3)(质量分数2%)的抛光液时,SiC的材料去除速率(MRR)由294 nm/h提高到605 nm/h,同时获得的晶圆表面粗糙度(Ra)为0.477 nm。然而,采用含有LPPs和ZrO_(2)的抛光液抛光SiC时,其材料去除速率和表面粗糙度都未得到明显改善。XPS测试结果表明,LPPs与光催化剂的协同作用增强了抛光液对SiC的氧化作用。UV-vis和PL测试结果显示,LPPs与不同光催化剂协同效果的差异主要与其光学性能有关。结论在光催化条件下,LPPs和TiO_(2)对单晶SiC-CMP具有协同增效的作用,然而LPPs和ZrO_(2)没有展现出协同增效的作用,即LPPs与光催化剂的协同作用可以改善SiC-CMP的性能,但是光催化剂的选择需要考虑LPPs的发光特性。

长余辉基适配体传感器在食品安全检测中的应用进展

食品工业的迅速发展离不开安全体系的构建。食品安全检测关系经济民生,是分析领域的研究热点。长余辉纳米粒子具有免原位激发和磷光可再生性,在激发光停止后持续发光,从而消除背景荧光干扰,是理想的光学传感元件。适配体是具有识别性能的寡核苷酸序列,兼具快速响应性、高特异性和灵敏度。二者通过基团键合可构建性能独特的探针,产生靶标刺激的信号变化,在食品安全检测领域享有壮阔前景。本文阐述了近年来长余辉基适配体传感器在食品安全检测中的研究进展。重点聚焦于实现传感器光学激活的设计策略,简要介绍了相应原理的研究应用,最后对于该技术面临的挑战和机遇进行讨论和展望,以推进食品安全检测的发展。

MgGa_(2)O_(4)∶Cr^(3+),Al^(3+)近红外发光长余辉纳米粒子的制备及发光性能研究

利用乙二醇辅助共沉淀法,制备了小尺寸近红外发光Al^(3+)共掺杂镓酸镁(MgGa_(2)O_(4))∶0.3%Cr^(3+)(MGO∶0.3%Cr^(3+),Al^(3+))长余辉发光纳米粒子(PLNP),考察了Al^(3+)掺杂对MGO∶0.3%Cr^(3+)晶体结构和光学性质的影响。研究结果表明,Al^(3+)掺杂对MGO∶0.3%Cr^(3+)的晶体结构无影响,但能提高MGO∶0.3%Cr^(3+)的发光强度。当Al^(3+)掺杂量为0.4%(摩尔分数)时,MGO∶0.3%Cr^(3+),0.4%Al^(3+)(Al^(3+)、Cr^(3+)相对于Ga^(3+)的物质的量比,摩尔分数)PLNP发光强度最强,余辉平均发光寿命从46.98s(MGO∶0.3%Cr^(3+))增大至78.75s(MGO∶0.3%Cr^(3+),0.4%Al^(3+)),平均粒径为(6.53±1.79)nm。本研究为制备小尺寸和高发光强度的PLNP提供了一种有效的方法。此外,高发光强度和长余辉寿命的MGO∶0.3%Cr^(3+),0.4%Al^(3+) PLNP为光学传感、成像和治疗等提供了材料支撑。

稀土掺杂长余辉纳米材料研究简述

长余辉纳米粒子(persistent luminescence nanoparticles,PLNPs)是一种特殊的发光材料,具有很长的余辉时间。尤其是稀土元素(rare earth elements,REE)掺杂PLNPs(REE-PLNPs)具有独特的4f电子构型、优异的物理化学稳定性、高的发光强度和量子产率以及长的余辉时间。通过调节REE掺杂离子的种类和浓度,可以改变REE-PLNPs的发射波长范围。虽然发光中心相同,但由于不同材料所属的晶格不同,不同PLNPs基质材料的光学性质往往不同。因此,改变基质材料以及稀土共掺杂离子的种类,以提高REE-PLNPs的发光强度,进而可对余辉性能进行优化,故REE-PLNPs在室内装修、安全标志、仪表显示、生物检测和成像、诊疗一体化等领域受到了研究者的关注。以镧系元素和Sc与Y等掺杂REE-PLNPs为例,介绍了REE-PLNPs的组成和余辉发光性能及其在光学性质方面的研究进展。评述了REE在改善PLNPs的发射波长和余辉强度方面的优势,展望了REE-PLNPs研究未来的发展方向。

基于光诱导电子转移的比率型发光传感器定量检测生物样本中的多巴胺

长余辉发光材料是一种光致发光材料,在激发停止后以光的形式将储存的能量缓慢释放出来,因其优异的光学性能而在生物传感和生物成像领域得到广泛应用.本文将发光性能优异的双发射长余辉纳米粒子Sr_(2.992)Mg_(0.9)Si_(2)O_(8)∶0.008Eu^(2+),0.10Mn^(2+)(SEM)和酪氨酸酶(Tyrosinase,TYR)共价偶联,开发了一种比率型发光传感器(SEM-TYR),其可避免自发荧光干扰和外部干扰,可用于高灵敏、高选择性检测生物样本中的多巴胺(DA).当DA存在时,酪氨酸酶将其氧化生成多巴醌,依据光诱导电子转移(PET)原理,SEM-TYR光致激发的电子部分转移至电子受体多巴醌,导致SEM-TYR中680 nm红色余辉猝灭.在最优实验条件下,双发射余辉猝灭比值Δ(I680/I460)与DA浓度呈良好的线性关系,线性范围为0.2~10μmol/L(R^(2)=0.9965),检出限为40 nmol/L.将该方法用于生物样本血清、尿液及汗液中DA的检测,回收率分别为94.8%~104.0%,91.3%~101.6%和97.4%~105.2%,RSD<6.8%(n=10).所开发的比率型发光传感器用于生物样本中DA的检测具有潜在的应用前景.

杂铜及部分高砷锑铜阳极的电解

本文介绍了杂铜及高砷锑铜阳极电解的技术条件和操作方法。特种对电铜表面长粒子和阳极钝化的发生原因和预防方法进行了探讨。

Zn_(1+x)Ga_(2-0.01-y)Ge_(x)O_(3x+4)∶0.01Cr,yBi长余辉纳米粒子的制备及其光学性质研究

采用水热合成及后续煅烧法制备了Zn_(1+x)Ga_(2-0.01-y)Ge_(x)O_(3x+4)∶0.01Cr,yBi(x=1~4,y=0~0.04)长余辉纳米粒子(PLNPs)。通过优化反应条件、Zn和Ge组成比例及Cr/Bi共掺杂比例,提高了材料的余辉发光性能。考察了煅烧温度和Cr/Bi共掺杂比例对PLNPs余辉发光性能和物相的影响,结果表明:当水热反应温度为180℃,水热反应时间为24 h,x取2,y取0.02时,样品的余辉发光性质最好。所制备的PLNPs的最佳组成为Zn_(3)Ga_(1.97)Ge_(2)O_(10)∶0.01Cr,0.02Bi,其具有尖晶石结构,余辉时间大于15 d,具有良好的长余辉发光性能。

时间分辨荧光侧流分析法检测水中17β-雌二醇

以偶联17β-雌二醇包被原(E2-BSA)的长余辉粒子(PLPs)为荧光供体,胶体金标记抗体为荧光受体,基于免疫识别和荧光共振能量转移原理,建立了E2的竞争型时间分辨荧光侧流分析方法。创新性地以余辉优良、微米级大尺寸的PLPs为荧光信号源,并利用其在硝酸纤维素膜上不迁移的特性将E2竞争物固定于检测区,巧妙解决了常规试纸对信号材料尺寸的纳米级别限制和小尺寸PLPs余辉短暂的矛盾;采用低功率紫外灯为激发光源,以智能手机实现时间分辨荧光(TRF)模式荧光采集,有效去除试纸荧光背景干扰进而提高信噪比。该时间分辨荧光侧流分析(TRF-LFA)法对E2的检出限为0.1 ng/mL,比胶体金侧流分析(CG-LFA)降低了2个数量级,且特异性良好,30 min可完成检测。将该方法应用于水中E2的检测,与HPLC-FLD法的结果一致。

In vitro and in vivo suppression of hepatocellular carcinoma growth by midkine-antisense oligonucleotide-loaded nanoparticles

AIM:To synthesize antisense oligonucleotides (ASODNs) of midkine (MK), package the ASODNs with nanoparticles, and to inhibit hepatocellular carcinoma (HCC) growth using these nanoparticles.METHODS: HepG2 cell proliferation was analyzed in vitro using the 3-(4,5-dimethythiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2Htetrazolium, inner salt assay. The in vivo activity of nanoparticles delivering the MK-ASODNs was analyzed by histopathological and immunohistochemical staining and quantitative real time polymerase chain reaction (PCR). RESULTS: The in vitro proliferation of HepG2 cells was signif icantly inhibited by the nanoparticles packaged with MK-ASODNs (NANO-ASODNs). Furthermore, the NANO- ASODNs signif icantly inhibited the growth of HCC in the mouse model. CONCLUSION: NANO-ASODNs can significantly suppress the growth of HCC in vitro and in vivo.

Effect of Electroacupuncture on Platelet-derived Growth Factor and the Ultrastructure of Mitochondria in Rats with Diabetic Gastroparesis

Objective To observe the effect of electroacupuncture(EA)at the pressure points Zu San Li(ST36),San Yin Jiao(SP6)and Liang Men(ST21)on platelet-derived growth factor(PDGF)and the ultrastructure of mitochondria in rats with diabetic gastroparesis(DGP).Methods Sixty Sprague Dawley(SD)rats were randomly separated into a normal control group(NC,n=10)and a modeling group(n=50).Rats in the modeling group received an injection of 2%streptozotocin(STZ)and a high-fat and highglucose diet for eight weeks to establish a DGP rat model.At the same time,blood glucose and a general symptom score were recorded every week.After modeling,30 successfully modeled rats were randomly separated into the following groups:the DGP group(n=10),the EA group(n=10)and the metoclopramide(MP)group(n=10).After three weeks of intervention,the gastrointestinal propulsive rate was measured by measuring the optical density(OD).The concentration of Ca2+was determined by fluorescence immunoassay,and levels of serum insulin(INS)and PDGF were determined by ELISA.The ultrastructure of mitochondria was observed with transmission electron microscopy.Results(1)After intervention,levels of blood glucose and the general symptom score were greatly decreased in the EA group compared to the DGP group(P<0.01).Compared with the DGP group,the gastric emptying rate and the intestinal propulsive rate of the EA group was significantly improved(P<0.01),and there was no statistically significant difference between the EA and the NC groups.(2)Compared with the NC group,the levels of INS in the DGP group markedly decreased(P<0.05),but there was no significant difference of INS levels between the EA and the MP roups.(3)Compared with the DGP group,theconcentration of Ca2+in the EA and the MP groups significantly increased(P<0.01,P<0.05,respectively).(4)Compared with the NC group,the average OD of PDGF in the DGP group was significantly higher(P<0.01).Compared with the DGP group,levels of PDGF in the EA group increased significantly(P<0.01).(5)There were abundant mitochondria with a clear structure and complete cristae in the NC group.However,in the DGP group,mitochondria were severely swollen,partly vacuolated,and cristae were either fractured,absent,or shortened.In the EA group,mitochondria were slightly swollen,with clear cristae.Conclusions Electroacupuncture at the points Zu San Li(ST36),San Yin Jiao(SP6)and Liang Men(ST21)may improve gastric motility in DGP by up-regulating the amount of PDGF and improving the ultrastructure of mitochondria.

长程自旋粒子系统的大偏差与占位时间

研究具有长程交互作用的自旋粒子系统的大偏差理论 ,其中一个有特殊意义的结果是相应的变分原理 ,它表明这些系统的平稳Markov测度恰是相应大偏差速率函数的零点 .还从这种及其他观点讨论了相应Markov测度的惟一性 .然后 ,将这些结果应用于系统的占位时间 ,得到了新的大偏差与收敛结果 .

Bi_(2)Ga_(3.985)O_(9):1.5%Fe^(3+),Eu^(3+)长余辉材料的制备及光学性能研究

采用共沉淀法制备了Bi_(2-x)Ga_(3.985)O_(9):1.5%Fe^(3+),x Eu^(3+)(BGO:1.5%Fe^(3+),x Eu^(3+),x=0~2%)长余辉纳米粒子(PLNP),详细研究了Eu^(3+)掺杂浓度及煅烧温度对BGO:1.5%Fe^(3+)PLNP晶体结构和光学性质的影响。结果显示,最佳的PLNP组成为Bi1.99Ga3.985O9:1.5%Fe^(3+),1%Eu^(3+),属于莫来石晶体结构,发射峰处于798 nm,在900℃煅烧1 h时,可获得高纯度的BGO:1.5%Fe^(3+),1%Eu^(3+)PLNP,其平均电子陷阱能级深度为0.676 eV。与Fe^(3+)单掺杂BGO:1.5%Fe^(3+)PLNP相比,Eu^(3+)共掺杂BGO:1.5%Fe^(3+),1%Eu^(3+)PLNP后,荧光寿命(τ_(av))从13.77 s增大至15.56 s,余辉发光时间从3 h延长至8 h以上。由于共掺杂BGO:1.5%Fe^(3+),1%Eu^(3+)PLNP中存在从Eu^(3+)到Fe^(3+)的能量传递,共掺杂PLNP的余辉强度增大,发光时间延长。制备了长波长发射、具有余辉发光性能的BGO:1.5%Fe^(3+),1%Eu^(3+)PLNP,该材料在生物成像、疾病检测及生物传感等领域具有巨大的应用潜力。

Cr掺杂镓铟酸锌长余辉纳米粒子的制备及生物传感应用

通过水热法合成了不同含量In离子掺杂的ZnGa_(1.99-x)In_(x)O_(4)∶Cr_(0. 01)^(3+)长余辉纳米粒子(PLNPs)。通过In掺杂和改变反应pH条件,PLNPs的余辉强度和时长明显改善,近红外余辉时间超过96h,平均粒径为15.36nm。实验结果表明,PLNPs的余辉强度被多巴胺猝灭,PLNPs的相对余辉强度(F_(0)-F)/F_(0)与多巴胺浓度在0.005~20μmol/L范围内呈良好的线性关系,线性回归线方程为y=0.1789x+0.4427,相关系数R^(2)=0.9974,对多巴胺的检出限为0.0024μmol/L,其在生物传感领域有应用潜力。

Changes of Circulating Platelet-Derived Growth Factor and Granulocyte Colony-Stimulating Factor in Patients with Condyloma Acuminatum

Objective: To study the expression levels of platelet-derived growth factor (PDGF) and granulocyte colony-stimulatingfactor (G-CSF) in peripheral blood and their role in thepathogenesis of Condyloma acuminatum (CA). Methods: Sera were taken from 70 patients with Condylomaacuminatum and compared with 35 healthy controls. PDGFand G-CSF in serum were quantitated using a dual antibodysandwich enzyme-linked immunoabsorbent assay (ELISA). Results: Serum concentrations of PDGF and G-CSF weresignificantly increased in patients with Condylomaacuminatum (CA) compared to controls (P<0.001 and P<0.005respectively). Serum levels of PDGF and G-CSF correlatedwith clinical severity of CA, but no significant difference wasobserved between different duration of disease groups. Asignificant positive correlation was noticed between neutrophilcount and G-CSF levels (γ=0.38, P<0.001), and the neutrophilcount showed no significant correlation with PDGE Conclusion: The results indicated that increased expressionof PDGF an -CSF in peripheral blood might be involved in pathogenesis of CA.

The mitochondrial serine protease HtrA2/Omi cleaves RIP1 during apoptosis of Ba/F3 cells induced by growth factor withdrawal

Interleukin-3 （IL-3） deprivation of the mouse pro-B cell line Ba/F3 induces cell death that is abrogated by B-cell lymphoma 2 （Bcl-2） overexpression, but remains unaffected by the pan-caspase inhibitor carbobenzoxy-valyl-analyl- aspartyl-[O-methyl]-fluoromethylketone （zVAD-fmk）. IL-3 withdrawal causes receptor-interacting protein （RIP）I cleavage into C-terminal fragments of 30 and 25 kDa, and only cleavage leading to the former was prevented by zVAD-fmk, siRNA experiments demonstrated that generation of the 25-kDa fragment was due to a Bcl-2-modulated release of the mitochondrial serine protease high temperature requirement protein A2 （HtrA2）/Omi. Accordingly, recombinant HtrA2/Omi efficiently cleaved mouse RIP1 in vitro, generating fragments matching those observed in IL-3-deprived Ba/F3 cells. The HtrA2/Omi cleavage site in mouse RIP1 was mapped to the intermediate domain and the corresponding N- and C-terminal fragments were impaired in their ability to activate nuclear factor-r,B, c-Jun N-terminal kinase and p38 mitogen-activated protein kinase. Interestingly, knockdown of HtrA2/Omi afforded pro- tection against IL-3 withdrawal-induced death in the presence of zVAD-fmk, demonstrating a role for HtrA2/Omi in caspase-independent cell death during growth factor withdrawal by cleaving RIP1.