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Bilinear system model of DC-DC converters is built, combined with the control objective and extending the system, closed-loop nonlinear control system model of DC-DC converters is found.

首先建立了DC-DC变换器双线性系统数学模型，结合控制目的进行适当变形，得到DC-DC变换器的闭环非线性控制系统模型。

In order to eliminate the influence caused by the nonminimum phase characteristic of a common Boost DC／DC converter, Viswanathan K has proposed a novel tristate Boost DC／DC converter. For enhancing performance, the statespace averaging model of this converter was first presented in this paper. Due to the nonlinear nature in this model, an inputoutput feedback linearization technique was adopted, and a complete controllable linear system was obtained. Then a statefeedback control strategy was designed based on this linear system. Simulation results show that the proposed control strategy can assure constant output voltage in a wide range, so as to realize the stability of the system during large fluctuation of power supply and load disturbance. Good dynamic performance can also be achieved.

针对 Viswanathan K为消除普通BOOST DC／DC变换器的非最小相位特性而提出的三态Boost DC／DC变换器，为进一步提高这种电路拓扑的性能，在建立了变换器状态空间平均模型的基础上，针对其多变量、非线性特点，采用输入输出线性化将其转化为一个完全可控的线性系统，在此基础上应用现有成熟的线性控制策略进行了控制系统的设计，并且采用MATLAB进行仿真验证，结果表明：这种非线性控制策略可以确保输出电压在大范围内恒定可调，且即使存在大范围扰动(输入电压和负载变化均较大)的情况下，系统也可以确保稳定性和良好的动态性能。

Furthermore, it is clear that when carrier signal h=0, closed loop PWM DC-DC converters are not well-posed and when some condition is satisfied, closed loop PWM DC一DC converters with P controller are well-posed.

然后利用该结果对PWM型DC-DC降压变换器的适定性的研究表明当载波信号h=O时闭环PWM DC-DC 变换器总是不适定的，当载波信号h的参数和比例控制器的参数满足一定的条件时，比例控制的闭环PWM DC-DC变换器是适定的。

A novel phase-shifted zero-voltage and zero-current switching PWM DC/DC full-bridge converter is presented in this thesis, which is based on the groundwork of summarization of the development of Power Electronics in recent years and lucubration in theoretical basis of modern high frequency soft switching power convert technique and analysis of operation principle, characteristic of the circuit and inherent drawbacks of the traditional phase-shifted zero-voltage switching PWM DC/DC full-bridge con...

本文在对近年来电力电子学科的发展高度综述和对现代高频软开关功率变换技术理论基础深入研究的基础上，对传统的移相控制ZVS PWM DC／DC全桥变换器的工作原理、电路特性、存在的缺点进行了分析，在此基础上提出了一种改进型的移相控制ZVZCS PWM DC／DC全桥变换器。

So analyzing the phenomenon of unstable action and subharmonic of DC/DC converter from the angle of linear theory and definiteness theory can not meet the increasing requirement of control performance of DC/DC converter.

因此，仅仅从线性论和确定论角度去分析DC／DC变换器中的不稳定及次谐波现象已不能满足对DC／DC变换器控制性能日益提高的要求。

Measure character: Frequency limits: CH1:dResolution of C ～ 225MHz frequency: 10 / second time-interval resolution : N/A measures speed: Can amount to 200 times measure / the second mixes in limits of the voltage on GPIB sensitivity : DC ～ 100MHz: 200MHz of ～ of 5Vac+dc 100MHz of 20mVrms ～±: 225MHz of ～ of 5Vac+dc 200MHz of 30mVrms ～±: Input of 5Vac+dc of 40mVrms ～± adjusts:(CH1 chooses) impedance, coupling: 1M Ω or 50 Ω, ac or Dc are low connect filter: 100kHz, but switch attenuation:× 1 or reference of × 10 exterior time base inputs: 1, 5, 10MHz sparks: CH1, to rising / drop the edge sparks, the percentage that uses signal n or absolutely voltage install n, setting sensitivity mixes to low, medium or tall gate start: Automatic, the hand is moved (setting gate time or resolution digit); Exterior, defer interface: Standard GP-IB(IEEE 488.1 and 488.2), take; of SCPI compatible language to say RS-232 power source only: 10 ％ of 100-120VAC ±, 50, 60 or 10 ％ of 400Hz ± 10 ％ of 220-240VAC ±, 50 or 10 ％ of 60Hz ± are suttle: 3kg dimension: 348.3mm of × of 212.6 × 88.5H

测量特征：频率规模：CH1：dc～225MHz 频率分辨率：10位/秒时候距离分辨率：N/A 测量速度：可达200次测量/秒在GPIB上电压规模和灵敏度： DC～100MHz： 20mVrms～±5Vac+dc 100MHz～200MHz：30mVrms～±5Vac+dc 200MHz～225MHz：40mVrms～±5Vac+dc 输入调节：(CH1选择)阻抗，耦合： 1MΩ或50Ω，ac或dc 低通滤波器： 100kHz，可切换衰减：×1或×10 外部时基参考输入： 1，5，10MHz 触发： CH1，对回升/回升沿触发，用信号电平的百分数或相对电压设置电平，设置灵敏度至低、中或高闸门和启动：主动，手动(设置闸门时候或分辨率位数)；外部，延迟接口：尺度GP-IB(IEEE 488.1和488.2)，带SCPI兼容说话；只讲RS-232 电源：100-120VAC±10％，50，60或400Hz±10％ 220-240VAC±10％，50或60Hz±10％净重：3kg 尺寸：212.6×88.5×348.3mm

DCs acquired by our reformed methods express both CD83 and CD 14 molecules highly, and have a higher density than other domestic reports. The higher TNF in DCs culture medium of HC patient suggests DCs in patient still have antigen presenting ability and by optimization the culture medium would improve its presenting ability and have a potential value in design and application individual vaccine. Although antigens pulsed DCs have a decrescent antigen presenting ability but BCG HSP70 could induce its mature and improve its presenting ability. Suggests BCG HSP70 would be a useful mature inducer. Lymphocytes primed by DCs based HC vaccine have the specific cytotoxicity against HCC lines. The CTL after freezing and anabiotic could prophylaxis and therapy HC xenograft on nude mouse. The results also suggests that CD4〓 lymphocytes play a important role in HC with a good differentiation and would be useful in treatment this kind of HC. After being activated by Peptide LLNQHACAV of hAFP and apoptotic HCCs pulsed DCs respectively, the culture medium of activated lymphocytes both contains a high level Th1 cytokines IL-12 and TNF. Primed lymphocytes appeared a characteristic of NK cells. DCs not only inhibited the growth of human HCC and other cancer cells in vitro but also prevented the growth of HC xenograft on nude mouse in vivo. There are at least three kinds of mechanism playing important role in DC based vaccine ,there are inhibition of DCs, HC specific CTL and cytokines pathway.

诱导出的DC共同表达CD83和CD14分子，CD83分子表达明显高于国内报道；肝癌患者DC培养上清中TNF水平高于健康人，提示肝癌患者DC仍具一定的抗原呈递能力，适当调控可使其行使APC功能，以期在肝癌个体化疫苗中发挥作用；DC负载肝癌可溶性抗原后，抗原呈递能力降低，BCG HSP70可促进DC成熟，增加其抗原呈递能力，预示BCG HSP70有可能成为促进DC活化和成熟的另一重要分子；肝癌DC疫苗在体外诱导肝癌特异性淋巴细胞，活化的淋巴细胞在体外对肝癌细胞的杀伤以特异性CTL为主，同时分泌较高水平Th1型细胞因子IL-12和TNF，并抑制4种肝癌细胞生长；冷冻复苏后的肝癌特异性淋巴细胞可以预防和抑制人肝癌裸鼠皮下移植瘤，提示DC负载肝癌可溶性抗原后诱发的MHC-Ⅱ类限制性CD4〓T细胞有可能在分化程度高的肝癌治疗中发挥作用；用DC和HLA-A2〓DC分别负载凋亡肝癌细胞和hAFP218-226位LLNQHACAV HLA-A2限制性九肽，在体外诱导肝癌特异性淋巴细胞，活化后的CTL细胞分泌较高水平的Th1型细胞因子IL-12和TNF，并具较强杀伤活性，此CTL同时具备NK细胞特征；DC对肿瘤细胞的抑制作用可能是通过吞噬实现的，Fas-L在DC抑制中也起一定作用；DC对人肝癌裸鼠皮下移植瘤的抑制率为97％；在肝癌DC疫苗的作用中，至少联合3种以上机制，即通过DC的直接作用、肝癌特异性CTL和细胞因子途径直接或间接地杀伤和抑制肝癌细胞。

Get high purity DCs by Cultured plastic-adherent monocytes isolated from healthy human peripheral blood with GM-CSF and IL-4 for 7 days. To observe the morphology of DCs by inverted phase contrast microscope ,electron microscope and laser confocal microscope. Analyse phenotype of DCs with flow cytometry. Investigate the endocytosis ability of DCs as a group by Horseradish peroxidase endocytosis assay. To appraise allogeneic mixed lymphocytes reaction of DCs by MTT reduction assay. Analyse the levels of IL-12 and TNF in liquids of cultured medium by ELISA and MTT reduction assay respectively. Soluble antigens of HCCs was obtained by 3 freeze-and-thaw cycles. Biological characteristics of HC soluble antigens pulsed DCs were monitored by flow cytometry. According to MTT reduction assay estimated the cell proliferation of self lymphocytes activated by HC antigens pulsed DCs. Get high purity BCG HSP 70 protein by SDS-PAGE electrophoresis and determined its biological activity with ELISA. Analyse phenotype of antigen pulsed DCs primed by BCG HSP70 with flow cytometry. By MTT reduction assay estimated the cell proliferation of self lymphocytes and the MLR of DC based vaccine. Analyse expression of HLA-DR molecule on surface of HCC lines. The IFN-γ mRNA in lymphocytes after actived by DC vaccine and the Fas-L expression on DC and DC vaccine primed lymphocytes were detected by in situ hybridization and flow cytometry respectively. Specific cytotoxity lysis of T lymphocytes and nonspecific inhibition of liquids in culture medium against HCC lines were also tested. Detect expression of hAFP on four HCC lines with Cell-ELISA. Induce apoptosis of HCCs with actinomycin-D. Interaction of DCs and apoptotic cells was observed under transmission electron microscope. Growth inhibition test of DC against HCC lines was also performed. Establish the nude mouse model bearing human HC xenografts and indentify the characteristic of tumour by histochemistry and immunohistochemistry techniques. Prevent and treat transplanted human HC on nude mouse with Freezing and anabiotic HC specific lymphocytes.

用GM-CSF和IL-4从健康人外周血诱导DC；分别用倒置相差显微镜、电子显微镜及激光共聚焦显微镜观察DC形态；流式细胞术检测DC表型；HRP吞噬实验测定DC的群体内吞能力；MTT法检测同种异体混合淋巴细胞反应；ELISA法和MTT法分别测定DC培养上清液中IL-12和TNF水平；冻融法制备肝癌细胞可溶性抗原；流式细胞术检测负载肝癌可溶性抗原后DC的生物学特性；MTT法检测DC负载肝癌抗原后对自身淋巴细胞增殖的影响；SDS-PAGE制备电泳纯化BCG HSP70并鉴定纯度，ELISA测定活性；流式细胞术检测负载抗原DC经BCGHSP 70活化后的表型；MTT法检测肝癌DC疫苗对自身淋巴细胞增殖的影响和混合淋巴细胞反应；流式细胞术检测肝癌细胞表面HLA-DR表达；MTT法检测肝癌DC疫苗对自身淋巴细胞的活化；原位杂交法检测肝癌DC疫苗活化后的淋巴细胞IFN-γmRNA表达；流式细胞术检测DC和肝癌DC疫苗活化后淋巴细胞表面Fas-L；MTT法分别检测肝癌DC疫苗活化的淋巴细胞和其培养上清对肝癌细胞的特异性杀伤和非特异性抑制作用；Cell-ELISA检测人肝癌细胞hAFP表达；MTT法检测负载AFP表位肽和凋亡肝癌细胞DC对自身淋巴细胞增殖的影响；ELISA法和MTT法分别测定活化后淋巴细胞培养上清中TNF和IL-12水平；肝癌细胞凋亡的诱导和检测；DC吞噬凋亡肝癌细胞后的电子显微镜观察；DC对肝癌细胞的生长抑制试验；人肝癌裸鼠皮下移植瘤动物模型的建立及其组织学和免疫组织化学鉴定；DC及肝癌特异性淋巴细胞预防和治疗人肝癌裸鼠皮下移植瘤；冻存和复苏后的肝癌特异性淋巴细胞预防和治疗人肝癌裸鼠皮下移植瘤。

Part II The experiment study on anti-tumour effect of dendritic cells derived from peripheral blood monocyte of patients with oral cancer after pulsed by tumour antigen in different ways. Collected 50ml peripheral blood from each patients and volunteers to induced DC in vitro. We parted the test group and control group into three subgroups respectively, untreated group A, freezed and thawn group B, RNA transfected group C. To group A, after induced DCs for five days , we added 200U/mlTNF-α in each hole and cultured on. To group B, we added protein antigen (DC/ tumor cells = 1 : 1 ,each hole) for 4h at 5d, and then added 200U/mlTNF-α in each hole and cultured on. To group C, transfected immature DC with tumor cell RNA(DC:RNA=1×105/ml: 5ug)at 5d, operated completely with the specification of invitrogen DMRIE-C reagents. After transfection we replaced transfection agent with complete medium, and then added 200U/mlTNF-α in each hole and cultured on.

第二部分口腔癌患者外周血来源的树突状细胞体外负载抗原后抑瘤作用的实验研究无菌采集20例口腔癌患者和20例健康志愿者外周血50ml，分离单个核细胞体外诱导培养DC，并将实验组和对照组细胞各分为三组，A组为未处理组，B组为冻融组，C组为RNA转染组。A组DC在培养5d后，每孔加入TNF-α200U/ml；B组DC培养第5d后，每孔中加入癌细胞蛋白抗原，使DC/肿瘤细胞=1：1，继续培养4h后，每孔加入TNF-α200U/ml；C组将培养至第5d的未成熟DC用肿瘤细胞RNA进行转染(DC：RNA=1×105/ml： 5ug，按照invitrogen DMRIE-C试剂说明书进行操作)，转染结束后用完全培基取代转染剂，每孔加入TNF-α200U/ml。

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The absorption and distribution of chromium were studied in ryeusing nutrient culture technique and pot experiment.

采用不同浓度K2CrO4(0，0.4，0.8和1.2 mmol/L)的Hoagland营养液处理黑麦幼苗，测定铬在黑麦体内的亚细胞分布、铬化学形态及不同部位的积累。

By analyzing theory foundation of mathematical morphology in the digital image processing, researching morphology arithmetic of the binary Image, discussing two basic forms for the least structure element: dilation and erosion.

通过分析数学形态学在图像中的理论基础，研究二值图像的形态分析算法，探讨最小结构元素的两种基本形态：膨胀和腐蚀；分析了数学形态学复杂算法的基本原理，把数学形态学的部分并行处理理念引入到家实际应用中。