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1.
为了充实河北雾灵山自然保护区的野生动物资源本底资料,提高监测能力和监测水平,雾灵山保护区自2015年开始将红外相机技术应用到野生动植物的资源调查和管护中。目前应用红外相机技术发现兽类5目10科14种,鸟类4目6科10种,掌握了区内主要物种猪獾(Arctonyx collaris)、狍(Capreolus)和勺鸡(Pucrasia macrolopha)的日活动节律,补充了保护区的本底调查资料,为保护区进一步开展金钱豹(Panthera pardus)、斑羚(Naemorhedus goral)和鸟类多样性等科学研究奠定了基础,为保护区制定关于野生动物资源的相关管护政策提供了科学依据。 相似文献
2.
双马来海松酸酯多元醇的合成研究 总被引:7,自引:0,他引:7
利用马来海松酸中酸酐和羧基反应活性的差异,合成了两种类型的双马来海松酸酯多元醇.测试了酯化产物的分子量、聚合度、粘度、羟值和官能度等理化参数;并对各产物的耐热性和红外光谱进行了讨论.研究结果表明,所有酯化产物均可作为耐热的多元醇原料使用. 相似文献
3.
森林可燃物的燃烧性与化学组成 总被引:14,自引:1,他引:13
从五种针叶树叶(白皮云杉、红松、兴安落叶松、黑皮油松、樟子松)以及六种阔叶树叶(柳树、白桦、杨树、黄波罗、水曲柳、蒙古栎)的春季和秋季样品的水分、灰分(水溶性和水不溶性)、醚抽提物、含氮量、含磷量的分析得出:兴安落叶松和柳树的可燃性最小。这一结果与热重分析所得结果相符合。 相似文献
4.
Sean G. Sanders DVM Russell L. Tucker DVM Rodney S. Bagley DVM Patrick R. Gavin DVM PhD 《Veterinary radiology & ultrasound》2001,42(4):291-296
Magnetic resonance imaging (MR) was used to make a diagnosis of equine nigropallidal encephalomalacia in a horse. Equine nigropallidal encephalomalacia is a neurodegenerative disease that has many characteristics with Parkinson-like diseases in humans. Historically, horses were euthanized based on clinical signs and exposure to the toxic weed, yellow star thistle (Centaurea solstitialis). Previously, the disease has only been confirmed on necropsy. MR imaging can provide accurate and sensitive visualization of typical lesions seen in the brain of horses affected with equine nigropallidal encephalomalacia. Lesions were seen on T1-weighted, T2-weighted and proton density images. There was no contrast enhancement following Gd-DTPA administration. Lesions seen on MR were confirmed at necropsy. Using MR to confirm a diagnosis of equine nigropallidal encephalomalacia will prevent unnecessary suffering of horses and expense to owners that would otherwise incur, while further diagnostics are performed. 相似文献
5.
Christopher L. Mariani DVM Simon R. Platt BVMS MRCVS Susan M. Newell DVM MS Scott P. Terrell DVM Cheryl L. Chrisman DVM MS EDS Roger M. Clemmons DVM PhD 《Veterinary radiology & ultrasound》2001,42(6):524-531
A 3-year-old neutered female mixed breed dog was examined because of severe, generalized seizure activity, tetraparesis, and encephalopathic signs. Cerebrospinal fluid (CSF) evaluation was unremarkable except for a mild increase in protein. Serum and CSF titers for infectious diseases were negative. Magnetic resonance (MR) imaging examination of the brain was performed and lesions were found within the cerebral gray matter of the temporal and parietal lobes. The lesions had increased signal intensity on T1, T2, and proton density-weighted images. There was mild inhomogeneous enhancement following intravenous contrast medium administration. Neurologic status improved and the seizures were well controlled, but the dog never regained normal mentation and euthanasia was performed 10 weeks after initial evaluation. At necropsy, severe cerebral cortical necrosis was found in the regions corresponding to the lesions seen on MR imaging examination. Large numbers of fat-containing macrophages (gitter cells) were found within these areas, and are thought to be responsible for the characteristic hyperintensity seen on the MR images. 相似文献
6.
David Lipsitz DVM Robin E. Levitski DVM Wayne L. Berry BVSc MMedVet 《Veterinary radiology & ultrasound》2001,42(1):14-19
Three dogs with multilobular osteochondrosarcoma of the skull were evaluated using magnetic resonance (MR) imaging. Spin echo T1, T2, proton weighted and post contrast T1W images were obtained with a 1.5 Tesla magnet. The MR imaging findings were similar in all three dogs with mixed signal intensities in the T1W, T2W and proton weighted images and fairly large areas of contrast enhancement in the post contrast T1W images. The extent of brain and soft tissue involvement were well delineated and provided useful information concerning surgical planning. MR imaging provided a useful method of evaluating dogs with skull tumors. 相似文献
7.
8.
吴志芳 《仲恺农业技术学院学报》2006,19(3):43-46
手工识别成像测井中的裂缝具有一定的主观性,不同的人可能会有不同的解释结果.作者介绍利用Hough变换自动识别裂缝的原理及其算法,并通过实例分析了其应用效果,结果表明,这种算法计算裂缝参数不仅精度可靠,还保证了裂缝参数拾取的唯一性,对实现井壁裂缝参数的完全自动解释有重要意义. 相似文献
9.
Susan J. Holcombe VMD MS Alicia L. Bertone DVM PhD David S. Biller DVM Valerie Haider DVM 《Veterinary radiology & ultrasound》1995,36(2):119-125
The purpose of this study was to define normal gross anatomic structures in the equine stifle with magnetic resonance images. Magnetic resonance (MR) images were made in sagittal, 15° supinated, transverse, and dorsal planes of two equine stifles. The MR images were scrutinized by comparing MR images to dissection specimens and frozen cross sections of stifle joints. Sagittal and 15° supinated images were the most valuable in assessing articular cartilage, subchondral bone, and soft tissue structures within the joint. Cranial and caudal cruciate ligaments, medial and lateral menisci, meniscotibial and meniscofemoral ligaments, long digital extensor tendon, and patellar ligaments were easily evaluated. MR images provided substantially more gross anatomical information than the currently available imaging modalities. 相似文献
10.
J. F. McConnell BVM&S DVR DipECDVI Cert. SAM MRCVS L. Garosi DVM S. R. Platt BVM&S 《Veterinary radiology & ultrasound》2005,46(1):1-10
The magnetic resonance imaging (MRI) findings of presumed cerebrovascular accident in 12 dogs are described. Fourteen lesions were seen, commonly (11 of 14) within the gray matter of the cerebellar hemispheres or vermis. Thirteen lesions were hyperintense on T2-weighted images (in 11 dogs) and one was hypointense. Eleven of 14 lesions were within the region supplied by the rostral cerebellar artery or one of its main branches and there was no, or minimal, mass effect. Contrast enhancement was only seen in six lesions and was mild in all. Gradient-echo images provided additional information in two dogs. The appearance of infarction in dogs with diffusion-weighted images (DWI) is similar to that in humans, and provided supportive evidence for the diagnosis of infarction in five dogs. The use of gradient-echo and DWI is recommended for the evaluation of suspected cerebrovascular accidents in dogs. Six of the 12 affected animals were spaniels or spaniel crosses, suggesting a possible breed predisposition. 相似文献