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1.
以水杨醛和对硝基苯胺为原料合成了Schiff碱水杨醛缩对硝基苯胺,将其与Co(Ⅱ)作用合成水杨醛缩对硝基苯胺钴配合物。通过红外光谱分析、元素分析、热重分析等方法对产物结构进行表征。并通过荧光光谱对配体、配合物荧光发光性质进行了研究。结果表明,配体水杨醛缩对硝基苯胺及其Co(Ⅱ)配合物CoL_2·5H_2O均有发光性能。  相似文献   

2.
本文报道用5-硝基水杨醛合成了5-硝基,N(对氟苯基)水杨醛亚胺Schiff碱,其结构用红外光谱和共振谱表征,并对其生物活性作了初步研究,发现该化合物具有比较好的抑菌能力。  相似文献   

3.
文章以5-硝基水杨醛为起始原料合成了3-氨基-5-硝基-2-苯并呋喃甲酸乙酯。通过单因素试验,研究了反应时间、碱的种类对成环反应的影响,提高了产品收率,为工业化生产提供了方法参考。  相似文献   

4.
5-硝基水杨醛分离纯化方法改良   总被引:13,自引:0,他引:13  
魏青  陈三平  潘瑞琪 《精细化工》2000,17(3):178-179
对 5 硝基水杨醛的分离提纯方法进行了改良研究 ,发现加入一定量的稀碱使 3 和 5 硝基水杨醛均完全转变成钠盐是实验成功的关键。进而利用两种钠盐在水中溶解度的差异 ,采用水抽提方法 ,先将 3 和 5 硝基水杨醛的钠盐以溶液形式分离开 ,再分别经酸化及重结晶处理 ,即得产率为 5 8 0 %的 5 硝基水杨醛 ,纯度经HPLC测定为 99 4 % ,其结构经元素分析、红外、紫外、核磁等确证。同时还得到产率为 35 0 %的 3 硝基水杨醛。  相似文献   

5.
双水杨醛类缩乙二胺席夫碱的合成及光谱性能   总被引:3,自引:0,他引:3  
以水杨醛为原料,通过硝化或溴化反应合成了3,5—二硝基水杨醛(p.m57℃~59℃),5—溴水杨醛((m.p104℃~105℃),3—硝基水杨醛(m.p124℃~127℃),和3—溴—5—硝基水杨醛(m.p148℃~149℃)收率分别为76.0%、81.8%、63.0%和80.5%用水杨醛及其衍生物同乙二胺反应制备出11种双水杨醛缩乙二胺席夫碱。采用~1H—NMR对合成的系列席夫碱进行了表征,通过紫外光谱测定席夫碱中苯环上不同取代基对紫外吸收波长的影响。  相似文献   

6.
5-硝基水杨醛缩-2-氨基-5-偶氮苯吡啶的合成   总被引:3,自引:0,他引:3  
用自制的5-硝基水杨醛设计合成了5-硝基,水杨醛缩-2-氨基-5-偶氯苯吡啶杂环类Schiff碱,其组成和结构已由元素分析和红外光谱所表征。  相似文献   

7.
用多聚磷酸改进Duff反应合成了5-硝基水杨醛,探讨了温度、时间、反应物用量等因素对5-硝基水杨醛产率的影响。结果表明较佳反应条件是:在对硝基苯酚为3.5 g的情况下,75%的多聚磷酸用量为30 mL,n(六亚甲基四胺)∶n(对硝基苯酚)=2∶1,反应时间为3.0 h,反应温度105℃,5-硝基水杨醛的产率可达68.1%。并对产品进行了红外检测,符合文献值的要求。  相似文献   

8.
孙宾宾  杨博 《应用化工》2015,(3):588-590
在超声辐射条件下,以1,3,3-三甲基-2-亚甲基吲哚啉和5-硝基水杨醛为原料,以甲醇为溶剂,合成了光致变色化合物1,3,3-三甲基-6'-硝基螺吲哚啉苯并吡喃,以甲醇为溶剂,在有机碱六氢吡啶存在下,将1-羟乙基-2,3,3-三甲基吲哚啉碘化物和5-硝基水杨醛通过"一锅煮"的方式,合成了光致变色化合物1-羟乙基-3,3-二甲基-6'-硝基螺吲哚啉苯并吡喃。实验证实,超声辐射显著的加快了螺吡喃类化合物的合成过程。  相似文献   

9.
《应用化工》2022,(3):588-593
在超声辐射条件下,以1,3,3-三甲基-2-亚甲基吲哚啉和5-硝基水杨醛为原料,以甲醇为溶剂,合成了光致变色化合物1,3,3-三甲基-6'-硝基螺吲哚啉苯并吡喃,以甲醇为溶剂,在有机碱六氢吡啶存在下,将1-羟乙基-2,3,3-三甲基吲哚啉碘化物和5-硝基水杨醛通过"一锅煮"的方式,合成了光致变色化合物1-羟乙基-3,3-二甲基-6'-硝基螺吲哚啉苯并吡喃。实验证实,超声辐射显著的加快了螺吡喃类化合物的合成过程。  相似文献   

10.
查尔酮类化合物是合成黄酮类药物的重要中间体,而且它本身也具有广泛的药理活性。在稀碱催化下,于75~80℃反应1.5h,苯乙酮分别与水杨醛、5-氯水杨醛、5-硝基水杨醛进行交叉羟醛缩合反应,合成了其中两个鲜见文献报道的查尔酮类化合物,产物通过元素分析、IR、1 H NMR、MS进行了结构确证。  相似文献   

11.
2,3,6-三甲基苯酚一步氧化制备2,3,5-三甲基-1,4-苯醌相对于传统的磺化-氧化法具有产品收率高、过程简单、条件温和以及环境友好等特点。本文针对2,3,6-三甲基苯酚一步氧化制备2,3,5-三甲基-1,4-苯醌的均相催化氧化和非均相催化氧化工艺进行了综述,对两种工艺的发展过程及研究现状进行了评价及总结。详细讨论了不同方法和路线在催化活性、选择性以及产品分离和催化剂回收等方面的优缺点,简要分析并总结了2,3,6-三甲基苯酚一步氧化研究的发展规律和最新动态,展望了以非均相催化反应机制为重点的微观机理研究和以提高催化剂循环稳定性、降低制备成本为重点的工业化探索两个潜在的发展方向。  相似文献   

12.
Biosorption may be simply defined as the removal of substances from solution by biological material. Such substances can be organic and inorganic, and in gaseous, soluble or insoluble forms. Biosorption is a physico‐chemical process and includes such mechanisms as absorption, adsorption, ion exchange, surface complexation and precipitation. Biosorption is a property of both living and dead organisms (and their components) and has been heralded as a promising biotechnology for pollutant removal from solution, and/or pollutant recovery, for a number of years, because of its efficiency, simplicity, analogous operation to conventional ion exchange technology, and availability of biomass. Most biosorption studies have carried out on microbial systems, chiefly bacteria, microalgae and fungi, and with toxic metals and radionuclides, including actinides like uranium and thorium. However, practically all biological material has an affinity for metal species and a considerable amount of other research exists with macroalgae (seaweeds) as well as plant and animal biomass, waste organic sludges, and many other wastes or derived bio‐products. While most biosorption research concerns metals and related substances, including radionuclides, the term is now applied to particulates and all manner of organic substances as well. However, despite continuing dramatic increases in published research on biosorption, there has been little or no exploitation in an industrial context. This article critically reviews aspects of biosorption research regarding the benefits, disadvantages, and future potential of biosorption as an industrial process, the rationale, scope and scientific value of biosorption research, and the significance of biosorption in other waste treatment processes and in the environment. Copyright © 2008 Society of Chemical Industry  相似文献   

13.
振动丝法测定常压和加压下液体的黏度和密度   总被引:5,自引:0,他引:5       下载免费PDF全文
马沛生  周清  杨长生  夏淑倩 《化工学报》2004,55(10):1608-1613
介绍了自行研制的高温高压振动丝黏度密度仪的构造和测定原理,并以正戊烷作为实验流体对仪器的可靠性和准确性进行了测试.测定了环己烷在323.15~413.15 K温度范围内、正辛烷在313.15~393.15 K温度范围内、苯在303.15~445.15 K温度范围内压力分别为常压和6.10 MPa、正庚烷和异辛烷在298.15~403.15 K温度范围内压力分别为常压和5.10 MPa下的黏度与密度,并分别对不同压力下的黏度、密度数据进行了关联.  相似文献   

14.
将木质素作为一种有机颗粒填料添加到热塑性塑料中,可解决造纸黑液资源化利用、石油原料日渐紧张以及环境污染加剧等严峻问题。而木质素与热塑性塑料之间相容性直接影响木质素在塑料工业中的应用与发展。首先简要概述了木质素结构与性质和木质素/热塑性塑料复合材料的性能分析,然后系统地阐述国内外研究木质素/热塑性塑料复合材料界面增容方法及其原理;增容方法按添加相容剂、改性木质素和改性塑料进行归类,并对3种增容方法进行比较分析;接着综述了木质素复合材料中增容方法的交叉复合使用;最后对未来木质素/热塑性塑料复合材料界面增容的研究方向以及思路进行了展望。  相似文献   

15.
Chlorophyll pigments present in canola seed, meal and crude and degummed oils were analyzed by high-performance liquid chromatography (HPLC) with a fluorescence detector. Chlorophylls a and b, low levels of pheophytin a, and occasionally traces of pheophorbide and its methyl ester were present in canola seed. Meals and oils contained magnesium-deficient chlorophyll pigments such as pheophorbide a, methylpheophorbide a, pheophytins a and b, and pyropheophytins a and b but not chlorophyll a or b. The amounts of chlorophyll pigments were oil > seed >> meal. Both crude and degummed oils contained pheophytin a and pyropheophytin a as main components, but the ratio of pyropheophytin a to pheophytin a was markedly higher in degummed oils. No pheophorbides were detected in degummed oils. These results suggest that oil processing steps such as extraction and degumming affect the composition of chlorophyll pigments. Publication No. 678 Canadian Grain Commission.  相似文献   

16.
塑料挤出机螺杆,机筒耐磨损,耐腐蚀的强化与应用   总被引:4,自引:0,他引:4  
李金钊 《中国塑料》1999,13(9):83-88
对塑料挤出机,注塑机螺杆,机筒的磨损,腐蚀原因及提高螺杆,机筒耐磨损,耐腐蚀的方法、制造与应用作了较详尽的介绍。  相似文献   

17.
工业生产中物位测量的探讨与研究   总被引:4,自引:0,他引:4  
在工业生产中常常会遇到常温,常压和一般介质的液位,料位和界面的测量,也会遇到高温,高压,易燃易爆,腐蚀性较强的液位,料位和界面的测量。在工业生产中物位测量有接触式和非接触式测量。但应根据生产工况及技术要求来合理选用。  相似文献   

18.
Dryer design requires food properties, drying rate and mass-heat transfer coefficients. These values change continuously during drying due to changes in food fractions, particularly the water fraction. The high energy demand and costs allied to inefficient devices, creates a great need for new processing equipment. Along these guide-lines, several heat pump drying research projects were established at the Norwegian University of Science and Technology. The heat pump dryer provides high quality final product as its drying conditions can be controlled. Its efficiency and non-polluting operation come from closed air-refrigerant circuits and from its ability to fully recover the latent heat of moist air as it exits the drying chamber. Most of the above features are quite the opposite of the conventional dryer characteristics. Several experiments were made on heat pump drying of fruits and roots at temperatures from -22.5 to 40°C to obtain data and correlations on thermophysical properties, specific enthalpy and rehydration. Also, tests were done on drying rate, moisture content, drying constant, effective mass diffusivity and heat and mass transfer equations. The next important phase is the development of a simulation model to predict the performance and characteristics of the heat pump dryer plant. The objectives of the present work are to develop and lo test a heat pump dryer simulation model. The simulation provides results on the characteristics of both plant and components which are integrated by heat and mass transfer equations. The program has menus with click-on icons, input and output pop-up dialogue boxes. The usual commands such as, file-open, file-save, edit-delete are available in this program simply called Hpdryer. The model contains moist air psychrometric. natural and conventional refrigerant property libraries. Ammonia is a time-tested, self-alarming and natural refrigerant. It has been used extensively in the past, and it has better thermodynamic and transport properties than halocarbons. Safety is easily attained by design and its restrictive standards have helped increase its use in several countries. There are 36 ammonia installations in Norway and in the United Kingdom, including a drying plant. Ammonia has zero Odp, zero Gwp and the recent R&D has led to viable small-sale heat pump plants. Ammonia and dichlarodifluoromethane refrigerants were used in the test cases simulated by Hpdryer madel.  相似文献   

19.
Recent years have seen a marked rise in implantation into the body of a great variety of devices: hip, knee, and shoulder replacements, pacemakers, meshes, glucose sensors, and many others. Cochlear and retinal implants are being developed to restore hearing and sight. After surgery to implant a device, adjacent cells interact with the implant and release molecular signals that result in attraction, infiltration of the tissue, and attachment to the implant of various cell types including monocytes, macrophages, and platelets. These cells release additional signaling molecules (chemokines and cytokines) that recruit tissue repair cells to the device site. Some implants fail and require additional revision surgery that is traumatic for the patient and expensive for the payer. This review examines the literature for evidence to support the possibility that fibronectins and BMPs could be coated on the implants as part of the manufacturing process so that the proteins could be released into the tissue surrounding the implant and improve the rate of successful implantation.  相似文献   

20.
Imbalances in gut and reproductive tract microbiota composition, known as dysbiosis, disrupt normal immune function, leading to the elevation of proinflammatory cytokines, compromised immunosurveillance and altered immune cell profiles, all of which may contribute to the pathogenesis of endometriosis. Over time, this immune dysregulation can progress into a chronic state of inflammation, creating an environment conducive to increased adhesion and angiogenesis, which may drive the vicious cycle of endometriosis onset and progression. Recent studies have demonstrated both the ability of endometriosis to induce microbiota changes, and the ability of antibiotics to treat endometriosis. Endometriotic microbiotas have been consistently associated with diminished Lactobacillus dominance, as well as the elevated abundance of bacterial vaginosis-related bacteria and other opportunistic pathogens. Possible explanations for the implications of dysbiosis in endometriosis include the Bacterial Contamination Theory and immune activation, cytokine-impaired gut function, altered estrogen metabolism and signaling, and aberrant progenitor and stem-cell homeostasis. Although preliminary, antibiotic and probiotic treatments have demonstrated efficacy in treating endometriosis, and female reproductive tract (FRT) microbiota sampling has successfully predicted disease risk and stage. Future research should aim to characterize the “core” upper FRT microbiota and elucidate mechanisms behind the relationship between the microbiota and endometriosis.  相似文献   

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