6 kV高压异步电机软起动的硬件设计

对6 kV高压异步电机软起动硬件进行设计,包括主电路和控制电路的设计,通过晶闸管的选取以及对晶闸管均压电路、触发系统、保护电路、信号采集电路、电源电路等设计,完成6 kV高压异步电机的软起动要求,为系统设计提供硬件基础。     

正弦波同步触发电路及其晶闸管充电装置中的应用

正弦波同步触发电路是为晶闸管提供触发脉冲。阐述了正弦波同步触发电路的组成及各部分的作用,具体分析了一些出现故障的原因,并在十几年运行的经验基础上,提出了一些解决实际问题的方法。     

Hydrothermal synthesis and crystal structure study of two novel 3-D mellitates {Nd2[C6（COO）6] （H2O）6} and {Ho2[C6（COO）6]（H2O）6}

Two novel 3-D coordination compounds, Nd2[C6（COO）6]（H2O）6 （1）and Ho2[C6（COO）6]（H2O）6 （2）, were hydrothermaily synthesized from mellitic acid and neodymium perchlorate （or holmium perchlorate） in the alkaline aqueous solution and characterized with elemental analysis, TG, IR spectrum, and single crystal X-ray diffraction. The two compounds were isostructural and crystallized in the orthorhombic system, space group Pnnm, with a=1.3531 （4） nm, b=0.6687 （2） nm, c=1.0224（3） nm, V=0.92523（5） nm^3, Z=4, D=2.630 g/cm^3, F（000）=696.0, Goof=1.052. Final R indices [1 〉2∑（Ⅰ）]： R1=0.0195, wR2=0.0382 for 1; a=1.3411 （2） nm, b=0.6586（1） nm, c=1.0116（2） nm, V=0.8935（3） nm^3, Z=4, D=2.877 g/cm^3, F（000）=724.0, Goof=1.061. Final R indices [1 〉2∑（Ⅰ）]： R1=0.0200, wR2=0.0479 for 2. In the two compounds 1 and 2, the mellitic acid ligand, in which all the carboxylate groups were deprotonated, had only one kind of coordination mode to bridge metal ions to form four-connected three-dimensional diamondiod networks.     

Hydrothermal synthesis and crystal structure study of two novel 3-D mellitates {Nd_2[C_6(COO)_6](H_2O)_6} and {Ho_2[C_6(COO)_6](H_2O)_6}

Two novel 3-D coordination compounds, Nd2[C6(COO)6](H2O)6 (1) and Ho2[C6(COO)6](H2O)6 (2), were hydrothermally synthe-sized from mellitic acid and neodymium perchlorate (or holmium perchlorate) in the alkaline aqueous solution and characterized with ele-mental analysis, TG, IR spectrum, and single crystal X-ray diffraction. The two compounds were isostructural and crystallized in the ortho-rhombic system, space group Pnnm, with a=1.3531 (4) nm, b=0.6687 (2) nm, c=1.0224(3) nm, V=0.92523(5) nm3, Z=4, D=2.630 g/cm3, F(000)=696.0, Goof=1.052. Final R indices [I >2Σ(I)]: R1=0.0195, wR2=0.0382 for 1; a=1.3411(2) nm, b=0.6586(1) nm, c=1.0116(2) nm, V=0.8935(3) nm3, Z=4, D=2.877 g/cm3, F(000)=724.0, Goof=1.061. Final R indices [I >2Σ(I)]: R1=0.0200, wR2=0.0479 for 2. In the two compounds 1 and 2, the mellitic acid ligand, in which all the carboxylate groups were deprotonated, had only one kind of coordination mode to bridge metal ions to form four-connected three-dimensional diamondiod networks.     

定径机传动装置晶闸管经常击穿的解决方法

分析了无缝厂定径机组主传动调速装置晶闸管经常击穿的原因,是国产晶闸管与61LA70的触发电路不匹配,在逆变时晶闸管有时触发不开,造成换相失败产生很大的短路电流使晶闸管击穿。由于定径机不需要频繁正反转和快速停车,通过PLC控制调速装置正、反组脉冲的开通与封锁,使装置不进入逆变状态,避免了逆变失败,解决了晶闸管经常击穿的问题。     

遗漏脉冲检测报警电路

在冶金企业中有不少电子设备,例如同步电机的励磁系统,晶闸管直流电机调速系统等。这些电子设备中的脉冲电路易产生遗漏(丢失脉冲)现象,往往山于缺少遗漏脉冲检测报警电路,系统仍在继续带病工作,造成不应有的损失。为此,我们采用双极型单时基集成电路5G1 555设计、制作了一台遗漏脉冲检测报警电路。该电路可以有效地检测出脉冲电路遗漏脉冲的故障,并用发光二极管LBD(红色)显示,以便维修人员及时停机检查,避免故障扩大。现介绍如下:1 工作原理 如图1所示,当触发输入端S输入脉冲,Ui(t)处在“1”电平时,T1截止,电源Vcc通过电位器W向定时电…     

单片机控制的晶闸管脉冲触发电路

本文介绍用单片微型计数机构成晶闸管触发电路控制三相桥式全控变流电路的实现方法。重点阐述了电路的设计思想、硬件结构、程序编制以及提高本电路运行性能的措施,最后给出了电路运行时的实测结果。     

用过零周波触发方法提高变压器负载的功率因素

介绍了一种新的晶闸管（ＳＣＲ）触发方法－过零周波触发。并指出,将该法用于变压器负载的电路控制上,既可提高功率因素,又可避免变压器直流磁化问题。     

一种手性Zn(Ⅱ)配位聚合物的水热合成及晶体结构

通过水热技术制备了1种新的手性配位聚合物[Zn(Tar)(bipy)·5H2O](聚合物1,Tar为L-酒石酸根,bipy为2,2'-联吡啶),其结构经X射线单晶衍射鉴定.在水热反应过程中,酒石酸衍生物缩酮保护基发生水解.该聚合物属正交晶系,P2(1)2(1)2(1)空间群,晶胞参数a=0.664 61(13)nm,b=1.431 3(3)nm,c=1.912 8(4)nm,α=β=r=90°,V=1.819 6(6)nm3,Z=4,μ=1.414 mm-1,dcalc=1.678 g/cm3,F(000)=952,R1=0.045 7,ωR2=0.093 0.结构分析表明,酒石酸根桥连Zn(Ⅱ)形成一维配位聚合物手性链;2条平行一维链上的吡啶环以面对面的方式相互嵌入(质心距离为0.358 nm)形成新颖的梯状双链结构,5个结晶水之间存在氢键作用,通过共用边5聚环形成一维水链,而水链上的2个O又与未配位的羧酸根O通过氢键作用相连接形成三维超分子结构.     

应用于无线传感网频率合成器的0.5V低电压鉴频鉴相器设计

基于0.13μm CMOS技术设计了一个应用于无线传感网频率合成器、电源电压为0.5 V的鉴频鉴相器.它的功能是比较输入信号的频率和相位差,并输出一个与该差值成比例的电压.因电源电压是0.5 V,所以该电路采用低阈值晶体管.为了增大相位误差的检测范围和提高最大工作频率,该电路采用了脉冲锁存的结构.当输入信号频率为2 MHz时,测得的相位误差检测范围为-358°～358°.与传统数字鉴频鉴相器相比,该电路具有较快的捕获速度.当输入信号的频率为2 MHz且相位误差为0°时,电路的功耗为1.8μW,并且最大工作频率为1.25 GHz.     

[Ni(2,2′-bpy)2(H2O)]2[PMoⅥ7MoⅤ5VⅣ2O42]的水热合成与晶体结构

用磷钼酸做原料,在水热条件下合成了一种新的二帽二支撑的Keggin型多金属氧酸盐[Ni(2,2′-bpy)2(H2O)]2[PMoⅥ7 MoⅤ5 VⅣ2 O42],并通过元素分析、红外光谱、热重分析和X射线单晶衍射方法确定了该化合物的晶体结构.结构分析表明:该化合物属于三斜晶系,Pi空间群;晶胞参数a＝1.186 6(2)nm,b=1.242 3(3)nm,c=1.257 4(3)nm,α=71.10(3)°,β=74.38(3)°,γ=87.43(3)°,V=1.687 0(6)nm3,Z=1,R1=0.058 0,wR2=0.156 8.     

STUDY ON SYNTHESIS,CHARACTERIZATION AND STRUCTURE OF A NEW RARE EARTH COORDINATION COMPOUND WITH BENZOIC ACID

In this paper,a new rare earth benzoate coordination compound,[TbL_3(HL)(H_2O)]_2(HL=C_7H_6O_2=benzoic acid) is synthesized and characterized by elemental analysis DTA,TG,DTC,and IRspectra.The title compound crystallizes in triclinic,space.group P with a=9.148(1),b=11.460(2),c=13.506(2);α=112.76(1),β=91.83(1),γ=91.99(1)°;Z=1;V=1303.3.The final R factor is0.0235.The rare earth ion is nine-coordinated to form a distorted monocapped square antiprism.     

主传动功率单元局部过热诊断与消除

梅钢热轧精轧F3-F6主传动使用西门子Simadyn D直流传动装置,在轧制薄、宽板等特殊带钢时,电机电流过大,经常处于重载状态,致使晶闸管整流单元过热.经过对晶闸管电流、晶闸管GK极间电阻、触发脉冲的分析,并采取相应措施,保证了设备稳定.     

Fe-Cu-Nb-Si-B薄带的淬态纳米化与巨磁阻抗效应

使用较低的快淬速度(V =2 2m·s- 1 ) ,可以使Fe Cu Nb Si B薄带实现淬态纳米晶化。Fe Cu Nb Si B薄带析出αFe(Si)纳米相,其晶粒尺寸在淬态薄带Fe73Cu1 .5Nb3Si1 3.5B9中约为15nm ,在Fe71 .5Cu3Nb3Si1 3.5B9中约为10nm。添加Cu元素可以细化淬态薄带的晶粒。实验发现磁阻抗ΔZ/Z0 ,磁电阻ΔR/R0 ,磁电抗ΔX/X0 三条曲线交叉于一点,通过推导发现此现象具有必然性。淬态薄带Fe74 .5-xCuxNb3Si1 3.5B9的磁阻抗显示了较强的Cu含量依赖性。在快淬速度v =2 2m·s- 1 下,在x =1.5和x =3左右观察到磁阻抗峰值现象。     

2种同多钒氧酸盐的合成与磁性研究

在常规水溶液中合成了2种同多钒氧簇合物十钒酸盐[Na3(H2O)12][Ni(H2O)6]·[HV10O28](1)和[Na10(H2O)6][Co(H2O)6]·[VⅤ4VⅣ6O28](2).通过X射线单晶衍射对合成的化合物进行了表征.晶体结构分析表明:2种化合物均属单斜晶系,P2(1)群;化合物1晶胞参数a=0.902 04 nm,b=1.129 99 nm,c=1.175 15 nm,α=105.185 0°,β=97.327 0°,γ=100.838 0(10)°,V=1.114 15 nm3,Z=1;化合物2晶胞参数a=0.904 14 nm,b=1.130 84 nm,c=1.175 15 nm,α=105.18°,β=97.516 0°,γ=100.956 0(10)°,V=1.117 59 nm3,Z=1.并对2种化合物进行了磁性研究,表明磁性中心之间存在弱的反铁磁相互作用.     

Polynuclear Lanthanoid Complexes Containing Aluminium—The Structure of[HoAl(CF_3COO)_2(CF_3CHOO)(C_2H_5)_2(C_4H_8O)_2]_2 at 233K

[HoAl(CF_3COO)_2(CF_3CHOO)(C_2H_5)_2(C_4H_8O)_2]_2,Mr=1468.7,monoclinic,P 2_1/n,a=1.0084(4),b=1.8453(6),c=1.4501(6)nm,β=102.40(3)°,V=2.6355(1)nm~3,Z=2,D_c=1.81gcm~(-3),F(000)=1511,T=233K,Mo Kα radiation(λ=0.071069nm).R=0.052 for 6176 unique reflections[Ⅰ≥36(Ⅰ)].The structuralunits consist of dimeric molecules with the mixed ligand and central bimetallic atoms,which are polynuclearlanthanoid complexes containing aluminium.Ho-Ho'distance is 0.3619(1)nm.The coordination polyhedron ofHo can be described in terms of a distored bicap-prism.     

X波段单片低噪声放大器芯片

报道了X波段 0 .5 μmGaAsPHEMT全单片低噪声放大器芯片。该放大器芯片由四级级联放大电路构成。芯片面积为 2 .43× 1.85mm2 。该放大器芯片在通带内测试结果为 :在工作条件VD=5V(ID≤ 10 0mA)下 ,增益 >2 6dB ,噪声系数≤ 2 .2dB ,输入、输出电压驻波比 <1.6∶1,平坦度≤± 1dB ,1dB压缩功率≥ 15dB·m ,相位一致性≤± 3°,幅度一致性≤± 0 .5dB。芯片尺寸为 2 .43mm× 1.85mm。     

Synthesis and characterization of lanthanide complexes containing a bulky tridentate [N,N,O] Schiff base ligand

The lanthanide complexes containing a bulky tridentate [N,N,O] Schiff base ligand 3,5-But2-2-(OH)C6H2CH=N-8-C9H6N (HL) were synthesized and characterized. The reaction of anhydrous LnCl3 with NaL formed in situ in a 1:1 molar ratio in THF at room temperature afforded the lanthanide Schiff base dichloride complexes LnLCl2(DME) (Ln=Eu (1);Sm (2)). Complexes 1 and 2 can be used as precursors for the synthesis of the lanthanide cyclopentadienyl Schiff base derivatives. The reactions of complexes 1 and 2 with one equiv of NaCH3C5H4 in THF provided the desired products LnL(CH3C5H4)Cl(THF)·THF (Ln=Eu (3);Sm (4)) in good isolated yields. These complexes were characterized by elemental analysis, IR spectra, and X-ray structural determination, in the case of complexes 3 and 4. The crystal data of complex 3 are monoclinic, P21/c space group, a=1.3370(2) nm, b=1.5190(2) nm, c=1.8910(3) nm, β=109.846(4)°, V=3.6125(8) nm3, Z=4, Dc=1.416 mg/m3, μ=1.847 mm-1, F(000)=1584, R=0.0707, wR=0.1350. The crystal data of complex 4 are monoclinic, P21/c space group, a=1.3383(1) nm, b=1.5210(2) nm, c=1.8960(2) nm, β =109.878(3)°, V=3.6293(7) nm3, Z=4, Dc=1.407 mg/m3, μ=1.728 mm-1, F(000)=1580, R=0.0670, wR=0.1385.     

Synthesis, Characterization, and Reactivity of Amine Bis（phenolato） Cyclopentadienyl Lanthanide Complexes

（C5H5）3Ln（THF）reacted with amine bis（phenol） LH2 [ L = Me2NCH2CH2N {CH2-（2-O-C6H2-But^1-3-Me- 5）}2 ] in a 1：1 molar ratio in THF to generate the amine bis（phenolato） cyclopentadienyl lanthanide complexes LLn（C5H5） （THF）·（THF）,（Ln = La （1）, n =0; Ln = Sm（2）, n = 1） in high yields. Complexes 1 and 2 were fully characterized by elemental analysis, NMR （for 1） and IR spectra, and X-ray structural determination. The crystal data of complex 1 are monoclinic, P21/c space goup, a= 1.1595（1） nm, b = 1.8588（2） nm, c = 1.6647（1） nm, β = 98.490（2）°, V =3.5486（5） nm^3, Z =4, Dc = 1.338 mg· m^3,μ = 1240 mm^-1, F（000）= 1488, R =0.0249, wR = 0.0568. The crystal data of complex 2 are monoclinic, P21/c sp ace goup, a = 0.9692 （1） nm, b = 1.4583 （2） nm, c = 2.8192 （3） nm, = 96.805 （2）°, V = 3.9584 （7） nm^3, Z=4, Dc =1.340 mg · ma, μ = 1.524 mm^-1, F（000）= 1668, R =0.0346, wR =0.0756. The attempts failed to synthesize the amine bis（phenolate） lanthanide alkoxides by the reactions of complexes 1 and 2 with alcohols. The preliminary results revealed that complex 1 can initiate ε-caprolactone polymerization.     

Synthesis and Characterization of A Polynuclear Yttrium Trifluoroethoxide and Its Activity for Oligomerization of Phenyl Isocyanate

A polynuclear yttrium trifluoroethoxide was synthesized and its activity for the oligomerization of phenyl isocyanate was tested. Reaction of anhydrous YCl3 with CF3CH2ONa in a 1:3 molar ratio in THF at room temperature, after workup, gave complex 1 as colorless crystals. The composition of complex 1 is [Y(OCH2CF3)3]6ONa2(THF)12, which was identified by elemental analysis and 1H NMR. Further X-ray structure determination reveals that complex 1 is a polynuclear ion pair compound, [Y6(μ6-O)(OCH2CF3)18]2-[Na(THF)6] 2 (1). The crystal data of complex 1 are trigonal, P-3 space group, a=1.78440(14) nm, b=1.78440(14) nm, c=1.27395(12) nm, γ=120°, V=3.5129(5) nm3, Z=1, Dc=1.607 mg·m-3, μ=2.591 mm-1 (Mo Kα), F(000)=1710, R=0.067, wR=0.182. Preliminary results demonstrated that complex 1 is a highly effective catalyst for the oligomerization of phenyl isocyanate.