液冷服散热原理模型及其分析

目的 建立舱外航天液冷服散热的原理模型,提出其在工程设计中应遵循的基本原则。并以该原理模型为基础找到液冷服设计参数与散热量和散热效率的模化关系。方法 根据工程实际,对舱外航天液冷服散热过程进行分析。结果 液冷服各参数（管长、管径、流率和进口液温）对散热量和散热效率的影响是相互制约,相互作用的,因此各参数的合理取值是设计液冷服的关键。结论 该分析和研究对今后舱外航天液冷服的设计研制具有一定的指导意义     

应用潜热型功能热流体的液冷服散热性能分析

目的 研究潜热型功能热流体作为液冷服(LCG)冷却液的散热性能及其影响因素.方法 基于Pennes生物热方程建立人体躯干穿着液冷服的传热模型,通过对比各种条件下的液冷服散热量、液冷服效率、冷却液温度和人体皮肤温度等参数,分析液冷服的散热性能以及人体热舒适性.结果 相比以水为冷却液,潜热型功能热流体可以显著提高液冷服散热...     

通风温度对全身通风服热防护性能影响研究

目的研究通风温度对通风服装热防护性能的影响。方法通过分析"人体—全身通风服—环境"热系统传热传质过程,建立人体在通风条件下的热调节仿真模型,并且通过实验验证该分析模型的合理性。结果实验结果证实了模型的可靠性与准确性。通风流量较小时,较高的通风温度使人体平均皮肤温度上升很快,人体出汗更明显,可以达到更好的通风散热效果;较大流量下,降低入口通风温度可以更明显的减轻人体热应激程度,但人体出汗程度减弱,降低了通风服装对人体的蒸发散热效果,且此时需要较大的通风冷源。结论在一定通风流量下,当通风服装主要依靠蒸发散热时,通风温度较低反而不利于人体的散热。通风温度应根据通风服的散热机制以及通风流量适当确定。     

不同压力下通风服的除CO2除湿和散热

推导和分析了通风服头盔内的ＣＯ２分压同通风压力，流率及ＣＯ２排出率的关系方程，通过风流率同压力，除湿率和出口风湿关系方程以及通风流率同压力和散热率的关系方程，分析结果表明，为保持同样的头盔内ＣＯ２分压所需的质量流率随压力的降低呈直线降低；除湿所需的质量流率也随压力的降低而降低；低压下的散热效率由于除湿效率的提高而提高。这些方程可用于估算通风服流率和头盔流率，并可用于计算机自动计算通风散热量和排湿量     

利用暖体假人对液冷服散热特性的实验研究分析

目的：利用暖体假人对液冷服的各设计参数间的内在关系进行分析,同时对液冷服的散热特性进行评价分析。方法：温度舱内暖体假人着液冷服和隔热服,在不同的温度环境和不同的暖体假人体谢率条件下,改变服装设计参数,以获得液冷服在不同实验条件下进口液温、液体流率和液冷服散热量及温度比效率间的关系。并测量冷却液进出口温度,计算液冷服的实际散热量。结果：得到了液冷服在不同实验条件下进口液温、液体流率与液冷服散热量及温度比效率间的关系和液冷服的实际散热量,为服装设计了参数的合理性提供了评价依据。结论：验证了该舱外航天服的液冷服结构参数选取较为合理,揭示了液体流率受管道结构等条件的限制,合理调节流较窄,服装国度比效率不会很高,应主要靠调节进口液温来改变服装的散热量。     

舱外航天液冷服传热分析

简单介绍了舱外航天液冷服的结构、功能，分析了通风气体与液冷服基础服装间的对流换热、液冷服的传热传质过程，给出了液冷服传热传质数学模型。通过舱外航天服液冷通风系统与人体的联合热生理实验，该模型得到了验证，并为舱外航天服液冷通风系统的设计提供了依据。     

水下训练航天服固定配重设计仿真

目的通过仿真给出水下训练航天服的固定配重设计。方法基于水下训练航天服3D模型数据,参考人体国标参数,对照俄罗斯水下训练服,利用组合物体的力学性质,考虑水下训练航天服的实际应用,仿真分析固定配重对水下训练航天服姿态的影响。结果经过多参数计算仿真,最终确定水下训练航天服的固定配重参数。结论水下训练航天服设计仿真解决了固定配重的设计难题,对水下训练航天服的实际应用有一定的指导作用。     

登月服的热性能研究

目的计算代谢率为300 W和600 W情况下登月服的热性能。方法在考虑登月服外表面与太阳、月球、登月舱等的辐射换热,登月服内表面与人体之间的导热、对流、和辐射换热的基础上,建立了登月服换热模型;采用编程的方法进行计算。结果得到了代谢率为300 W和600 W情况下人体不同部位的皮肤温度和相关处通风气体和冷却液体的温度。结论在最冷和最热两种极限环境状态下,在登月服的上臂始端、躯干始端、大腿始端设置温度控制器,才能保证人体月面活动的热舒适。     

利用低真空环境在地面模拟载人航天器内部气体对流散热的探讨

为研究相应的模拟实验方法并建立载人航天器内部环境的地面模拟装置，克服地面上模拟微重力气体对流散热的困难，本文提出了地面以低真空技术减弱自然对流模拟载人航天器内啊对流热的实验方法，建立合适的试验舱和采用合适的实验方法，以便通过实验对环境控制与生命保障系统的设备作出评价。     

飞行员高空代偿服和FTF-2通风服通风散热性能评价

目的　探讨DC 7/ 7A高空代偿服和FTF 2通风服的通风散热性能 ,为其进一步改进设计提供理论依据。方法　 5名健康志愿者分别参加A组和B组实验。A组和B组实验的环境气候条件分别为干球温度 4 0℃和 4 5℃ ,相对湿度 4 5 %和 4 0 % ,实验时间90min和 12 0min。结果　热暴露期间 ,两组实验均可维持加权平均皮肤温度在人体舒适范围 (31 5～ 34 5℃ ) ,下身平均皮肤温度 33 1～33 8℃ ,但小腿皮肤温度无明显变化或仅轻度降低。A组和B组心率增值分别为 12 /min和 14 /min ,出汗量分别为 0 2 88± 0 0 5 6kg/ 1 5h和 0 4 4 5± 0 0 77kg/ 2h,蒸发率分别为 77 4 %± 3 6 %和 84 2 %± 2 4 %。两组实验的主观不适感觉均随着热暴露时间的延长而加重。结论　两种通风服的通风散热效果尚可 ,但有待重新设计某些重要部位通风孔分布的数量。当飞行员暴露热环境配穿这两种通风服实施通风时 ,仍将遭受轻度热应激并有一定程度的主观不适。     

Physiologic and pathologic calcifications and ossifications in the face and neck

The aim was to give a systematic presentation of physiologic and pathologic calcifications and ossifications in the face and neck with a special emphasis on clinical relevance. In a sometimes subacute setting one should recognize specific calcifications which often lead to important diagnoses such as fungal sinusitis or sclerosing labyrinthitis. In a more chronic situation intraocular calcifications in small children are pathognomonic for retinoblastoma. Juxtatumoral sclerosis of the laryngeal cartilage in laryngopharyngeal carcinoma is usually caused by tumor infiltration of the cartilage resulting in a higher tumor stage and, this way, has a major impact on the therapeutical strategy. Calcified lymph nodes are mainly unspecific but can be the result of tuberculosis or metastases of thyroid cancer. Cross-sectional imaging methods, most of all computed tomography, are ideally suited to reveal head and neck calcifications and ossifications, especially those which are clinically relevant.     

Head and neck infection and inflammation

This article discusses the imaging manifestations of infectious and inflammatory conditions of the head and neck. Special attention is paid to the sites, routes of spread, and complications of neck infections. Because the clinical signs and symptoms and the complications of these conditions are often determined by the precise anatomic site involved, anatomic considerations are stressed. Familiarity with the fascial layers, spaces of the neck, and the contents of each space is helpful for this discussion. The fascial layers of the neck are important barriers to infection, and once infection is established, the fascial layers play a part in directing its spread.     

Staging and surgical management of pancreatic and biliary cancer and inflammation

Management of benign and malignant diseases of the pancreas, liver, and biliary tract has made remarkable progress in the last two decades. Advances in minimally invasive surgery, interventional radiology, and diagnostic and therapeutic endoscopy have changed the treatment of common diseases such as cholelithiasis and more serious diseases such as pancreatic adenocarcinoma. Advances in biliary tract and pancreatic surgery have paralleled the advances in ultrasonographic imaging, CT, and MR imaging. This article outlines the surgeon's perspective on radiologic imaging and preoperative staging of benign and malignant biliary and pancreatic disease.     

细胞自噬与肿瘤发生发展

自噬是真核生物中一种高度保守的胞内降解途径.其主要通过溶酶体或液泡进行饥饿状态下的营养动员,清除受损蛋白质、细胞器和胞内病原体.自噬主要包括巨自噬、分子伴侣介导自噬(CMA)和微自噬.自噬已被证实与多种人类疾病相关,其在肿瘤发生发展中具有重要意义.近年研究中,对于自噬和肿瘤关系有了进一步的认识,该文就自噬分子机制、调控通路以及与肿瘤发生发展关系的研究进展作一综述.     

The thyroid and parathyroid glands. CT and MR imaging and correlation with pathology and clinical findings

Thyroid imaging approach is based on the preliminary clinical evaluation. Lesions that are smaller than 2 cm should be assessed with US, which is capable of discriminating masses as small as 2 mm and distinguishing solid from cystic nodules. US-guided FNAB provides tissue for cytologic examination of thyroid nodules. CT and MR imaging are indicated for larger tumors (greater than 3 cm diameter) that extend outside the gland to adjoining structures, including the mediastinum, and retropharyngeal region. Metastatic lymph nodes in the neck and invasion of the aerodigestive tract are also in the realm of CT and MR imaging. Thyroid nodules are categorized on scintigraphy as hot or cold nodules. Hot nodules are rarely malignant, whereas cold nodules have an incidence of 10% to 20% of malignancy. Calcifications (amorphous, globular, nodular, and linear) occur in adenomas and carcinomas and have no differential diagnostic features except for psammomatous calcifications, which are a pathognomonic finding in papillary carcinomas and a small percentage of medullary carcinomas. Papillary carcinoma is the most common malignant tumor (80%) followed by follicular (20% to 25%); medullary (5%); undifferentiated; anaplastic carcinomas (< 5%); lymphoma (5%); and metastases. Lymph node metastases are common in papillary carcinoma, 50% at presentation, and less common in follicular carcinomas. The metastatic nodes in papillary carcinoma may enhance markedly (hypervascular); show increased signal intensity on T1-weighted images (increased thyroglobulin content or hemorrhage); and reveal punctate calcifications. Localized invasion of the larynx, trachea, and esophagus occurs predominantly in papillary and follicular carcinomas; the incidence is less than 5%. Ectopic thyroid tissue may be encountered in the tongue (foramen cecum); along the midline between posterior tongue and isthmus of thyroid gland; lateral neck; mediastinum; and oral cavity. Goiter and malignant tumors, notably papillary carcinoma, may develop in ectopic thyroid tissue. Carcinomas may also arise in thyroglossal duct cysts, which develop from duct remnants between the foramen cecum and thyroid isthmus. Infectious disease of the thyroid gland is not common and the CT and MR imaging findings are similar as described under neck infection. Other types of inflammatory disorders including Hashimoto's thyroiditis, granulomatous thyroiditis, and Riedel's struma display no specific imaging features. Imaging studies may, however, be indicated to confirm a suspected clinical diagnosis and assess compromise of the airway (Riedel's struma). HPT is a clinical diagnosis in which hypercalcemia is the most important finding. Parathyroid hyperplasia, adenoma, and carcinoma represent underlying lesions. To relieve the patient's symptoms surgical extirpation is indicated. The surgical success rate without imaging is 95%. The indications for imaging studies vary but it is generally agreed that reoperation after a previous failed surgical attempt and suspicion of an ectopic parathyroid adenoma should be investigated by imaging. These consist of US, nuclear medicine studies, CT and MR imaging. US and technetium sestamibi scanning have the highest accuracy rate for localizing an adenomatous gland at and near the thyroid gland. Ectopic adenomas, particularly if they are located in the mediastinum, are preferrably investigated with CT and MR imaging with gadolinium and fat suppression. Carcinomas and parathyroid cysts are optimally evaluated by CT and MR imaging. On MR imaging adenomas are low in signal intensity on T1-weighted images, high in signal intensity on T2-weighted images, and enhance post introduction of gadolinium.