| 1 | 用于乙苯氧化脱氢制苯乙烯铝-硼催化剂:铝硼组成及制备方法对催化剂性能的影响(英文)显示文摘采用溶胶-凝胶(SG)法合成了不同摩尔比的Al-B催化剂(Al-10B与Al-35B).在450-500℃,乙苯(EB)接触时间为0.54 g-cat.s.cm-3的条件下,在氧气和水蒸气存在下对这些催化剂进行催化乙苯脱氢反应.利用NH3-TPD质谱分析了Al-B催化剂的酸性.扫描电镜图像显示,硼在氧化铝中负载量达15%(Al-15b)时仍分布很好,而在较高的硼含量(Al-25B和Al-35B)催化剂中观察到硼聚集.从本质上讲,在Al和Al-10B催化剂上观察到强度非常弱(Tmax≤125℃)的酸位,使得EB转化率和苯乙烯产率很低.另一方面,在Al-25B和Al-35B催化剂酸位较弱(Tmax≤180℃),因而EB转化率较高.然而,在弱-中等强度酸位的Al-15B催化剂上可以得到较高的苯乙烯产率(43.2%)和合理的EB转化率(46%).另外,采用共沉淀法(COP)和浸渍法(IMP)合成了Al-15B催化剂.IMP和COP催化剂的NH3-TPD-质谱分析结果发现,与NOx形成有关的酸位点在500℃时将EB转化率分别提高到66%和63%.然而,Al-B SG催化剂中的这些酸位降低,使得500℃时EB转化率为50%.当EB转化率为50%时,在Al-B IMP,Al-B COP和Al-SG催化剂上苯乙烯选择性分别为73%,82.5%和84%.因此,不同方法制备的Al-B催化剂,会产生不同强度和密度的酸位,从而影响苯乙烯的形成. | Nagaraju Pasupulety Muhammad A.Daous Abdulrahim A.Al-Zahrani Hafedh Driss Lachezar A.Petrov | 2019 | Chinese Journal of Catalysis2019，40，11： | 3 |
| 2 | Ultrasound screening of multifocal atherosclerosis: markers for coronary heart disease显示文摘Background and Objective The frequency of multifocal atherosclerosis (MFA) in patients with coronary heart disease (CHD) has not been thoroughly studied. The purpose of our study was to perform ultrasound screening for MFA in patients with coronary atherosclerosis and make evaluation of the sensitivity and significance of different atherosclerosis markers. Methods Using Color Dupplex Ultrasound (CDU), we studied 32 clinically healthy persons and 87 patients of the city of B with clinical data for CHD where we also performed coronarography. Results In patients with coronary atherosclerosis we found high frequency of carotid atherosclerosis (93%) and peripheral artery disease (PAD) (81%). We established verifiable thickening of the intima-media (IMT) of the common carotid artery (CCA) and common femoral artery (CFA) in patients with CHD. There is a correlation between the frequency of carotid and femoral stenoses and CHD proven by coronarography. Patients with CHD had a high relative risk to develop carotid (RR = 5) and peripheral atherosclerosis (RR=3.5) and high frequency of asymptomatic stenoses and thromboses of the internal carotid artery (86.9%) and femoral artery (78.3%), as well as aneurisms of the abdominal aorta (8.1%). Markers for CAD with high sensitivity were the atherosclerotic plaques of ICA (0.93) and CFA (0.81) as well as IMT of the CFA (0.84). Conclusions MFA are common among patients with CHD. Ultrasound diagnosis is the method of choice for simultaneous non-invasive screening of carotid, peripheral and MFA and provides sensitive markers for coronary atherosclerosis. The most sensitive and specific markers for CHD are the combination of the IMT and atherosclerotic plaques of CCA, ICA and CFA (100% sensitivity and 0.92 specificity). | Lachezar Grozdinski Mario Stankev Alexander Doganov | 2009 | Journal of Geriatric Cardiology2009，6，1： | 1 |
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