Nd∶YVO_4/YVO_4晶体的热键合及其激光性质的研究

为改善高功率激光器激光工作物质的热效应,本文采用热键合的方法研制了Nd:YVO4/YVO4复合晶体,键合晶体的波前干涉P-V值为0.082λ(λ=0.6328μm),键合面对波前的影响很小。它在LD端面连续泵浦条件下,从泵浦光到基频光的转换效率可达60%,特别当泵浦功率比较大时,键合晶体的输出功率比单块晶体有较大的提高。     

Performance of n-type silicon/silver composite anode material in lithium ion batteries: A study on effect of work function matching degree

In this paper, two types of silicon(Si) particles ball-milled from n-type Si wafers, respectively, with resistivity values of 1 Ω·cm and 0.001 Ω·cm are deposited with silver(Ag). The Ag-deposited n-type 1-Ω·cm Si particles(nl-Ag) and Ag-deposited n-type 0.001-Ω·cm Si particles(n0.001-Ag) are separately used as an anode material to assemble coin cells,of which the electrochemical performances are investigated. For the matching of work function between n-type 1-Ω·cm Si(nl) and Ag, nl-Ag shows discharge specific capacity of up to 683 mAh·g~(-1) at a current density of 8.4 A·g~(-1), which is40% higher than that of n0.001-Ag. Furthermore, the resistivity of nl-Ag is lower than half that of n0.001-Ag. Due to the mismatch of work function between n-type 0.001-Ω·cm Si(n0.001) and Ag, the discharge specific capacity of n0.001-Ag is 250.2 mAh·g~(-1) lower than that of nl-Ag after 100 cycles.     

激光二极管泵浦Nd:YVO4/YVO4复合晶体绿光激光器

采用一种新型的Nd:YVO4/YVO4复合晶体,利用V型折叠腔,研究了高功率激光二极管端面泵浦的Nd:YVO4/YVO4复合晶体激光器基频1.06 μm及倍频532 nm激光的输出特性.当泵浦功率为24.6 W时,获得1.06 μm激光的最大输出功率为11.7 W,光-光转换效率为48%.当泵浦功率为17 W时,获得了5.32 W的绿光输出,光-光转换效率达到31.3%.     

高效液相色谱-荧光检测法测定橄榄油中4种多环芳烃

建立了高效液相色谱-荧光检测(HPLC-FLD)测定橄榄油中苯并[a]蒽、屈艹、苯并[b]荧蒽、苯并[a]芘4种多环芳烃(PAHs)的分析方法。橄榄油样品经异丙醇稀释,采用具有π-π特异性作用的固相萃取柱净化,Agilent ZORBAX Eclipse PAH色谱柱(100 m m×2.1 m m,1.8μm)分离,以水-乙腈为流动相,梯度洗脱,实现了4种化合物的基线分离,并用基质匹配校准溶液进行外标法定量。4种多环芳烃的线性范围为2.4~40μg/L,相关系数(r)为0.999 0~0.999 9,方法的定量限为0.147~0.413μg/L,加标回收率为95.5%~103.2%,日内和日间精密度(RSD)分别为0.10%~1.69%和2.48%~2.93%(n=5)。该法具有灵敏度高、检出限低、重复性好等特点,适用于橄榄油中4种PAHs快速、准确的定量检测。     

糖蛋白糖基化位点及糖型的多重质谱分析

以糖蛋白核糖核酸酶B(RNase B)为研究对象,采用基质辅助激光解吸电离-串联飞行时间质谱(MALDI-TOF/TOF-MS)、傅里叶变换离子回旋共振质谱(FT-ICR-MS)的碰撞活化解离(CAD)和电子转移解离(ECD)多种质谱技术对RNase B的糖肽的完整信息进行解析.通过多种质谱相互验证,确定了RNase B的糖肽组分的氨基酸序列为SRNLTK、糖链结构为(HexNAc)2(Hex)5-(HexNAc)2(Hex)9及糖基化位点为第34位氨基酸残基.本方法为糖蛋白结构的全面解析提供了一种快速、有效、全面的研究思路.     

Cu3P纳米板阵列@泡沫铜三维骨架的原位构筑及其作为高性能锂金属负极

通过简单的原位生长法,将Cu3P纳米板阵列均匀负载在商业化的泡沫铜内部(NF?Cu3P@Cu),并用作锂金属负极的三维骨架载体材料。亲锂性的Cu3P纳米板阵列可以提供均匀且丰富的锂成核活性位点,诱导锂金属在NF?Cu3P@Cu内快速形核和均匀电沉积。同时,在电镀沉积锂时,Cu3P纳米板阵列会被锂化形成快离子导体Li3P,可以确保锂离子在复合负极中的快速均匀传输,从而有效抑制锂枝晶的形成。因此,获得的Li@NF?Cu3P@Cu复合负极材料在对称电池和全电池中,均表现出优异的循环稳定性。     

大流量采样高分辨气相色谱/高分辨质谱法测定大气中的多氯联苯和多溴联苯醚

建立了大流量空气采样高分辨气相色谱/高分辨质谱(HRGC/HRMS)同时分析测定大气样品中多氯联苯(PCBs)和多溴联苯醚(PBDEs)的分析方法。结果表明在采样过程中污染物没有发生穿透。通过添加 13C同位素标准物质进行评价,PCBs和PBDEs的加标回收率分别为60.7%～121.4%和69.9%～140.4%,均符合美国环保署相关方法的要求。PCBs和PBDEs的方法检出限分别低于0.019 pg/m3和0.189 pg/m3;色谱分离效果良好,可以满足大气样品中PCBs和PBDEs的监测需要。     

Study on optical characteristics of Nd:YVO_4/YVO_4 composite crystal laser

Thermal effect in crystals is the main obstacle blocking diode-pumped solid state laser to get high and stable output, power. Diffusion bonding crystal has been demonstrated to be an effective method to relieve the thermal lensing theoretically based on the numerical heat analysis to the end-pumped anisotropic laser crystal. The temperature distributions in Nd:YV04/YVO4 composite crystal and conventional crystal were analyzed and compared. The end-pumped Nd:YVO4/YVO4 composite crystal laser was designed and set up with 2-cavity. The maximum output powers of 9.87 W at 1064 nm and 6.14 W at 532 nm were obtained at the incident purnp power of 16.5 W. The highest optical-optical conversion efficiencies were up to 59.8% at 1064 nm and 37.2% at 532 nm respectively.     

气相色谱-串联质谱法测定婴儿奶粉中16种邻苯二甲酸酯类化合物

建立了气相色谱-串联质谱（GC-MS/MS）测定复杂基体婴儿奶粉中16种邻苯二甲酸酯类塑化剂的分析方法。奶粉样品以水溶解均质,乙腈提取,乙二胺-N-丙基硅烷（PSA）类型玻璃固相萃取柱净化,DB-5 MS UI气相色谱柱（30 m×0.25 mm×0.25 μm）分离,同位素稀释质谱法（IDMS）定量。比较了氧化铝/PSA和PSA两种固相萃取柱在不同洗脱条件下萃取16种塑化剂的回收率。最终选择PSA固相萃取柱,以正己烷-丙酮（60：40,v/v）作为洗脱溶剂,实现奶粉基体中16种塑化剂的净化。采用基质匹配同位素内标法定量,16种塑化剂在0.01~2.0 mg/kg范围内线性良好,线性相关系数（R²）大于0.9996,检出限和定量限分别是0.15~2.50 μg/kg和0.50~8.33 μg/kg,加标回收率为96.1%~104.0%,相对标准偏差（RSD）小于3.3%（n=5）,该方法灵敏度好、精密度高,适用于婴儿奶粉基体中16种塑化剂的痕量分析。     

Nd:YVO4/YVO4晶体的热键合及其激光性质的研究

为改善高功率激光器激光工作物质的热效应,本文采用热键合的方法研制了Nd:YVO4/YVO4复合晶体,键合晶体的波前干涉P-V值为0.082λ(λ=0.6328μm),键合面对波前的影响很小.它在LD端面连续泵浦条件下,从泵浦光到基频光的转换效率可达60;, 特别当泵浦功率比较大时,键合晶体的输出功率比单块晶体有较大的提高.