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Solvent extraction and separation of cobalt from leachate of spent lithium-ion battery cathodes with N263 in nitrite media 被引量:2
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作者 Yingnan Yang Yingjie Yang +5 位作者 Chunlin He Yuezhou Wei Toyohisa Fujita Guifang Wang Shaojian Ma Wenchao Yang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第5期897-907,共11页
To effectively separate and recover Co(Ⅱ) from the leachate of spent lithium-ion battery cathodes,we investigated solvent extraction with quaternary ammonium salt N263 in the sodium nitrite system.NO_(2)^(-)combines ... To effectively separate and recover Co(Ⅱ) from the leachate of spent lithium-ion battery cathodes,we investigated solvent extraction with quaternary ammonium salt N263 in the sodium nitrite system.NO_(2)^(-)combines with Co(Ⅱ) to form an anion [Co(NO_(2))_(3)]^(-),and it is then extracted by N263.The extraction of Co(Ⅱ) is related to the concentration of NO_(2)^(-).The extraction efficiency of Co(Ⅱ) reaches the maximum of99.16%,while the extraction efficiencies of Ni(Ⅱ),Mn(Ⅱ),and Li(Ⅰ) are 9.27%-9.80% under the following conditions:30vol% of N263 and15vol% of iso-propyl alcohol in sulfonated kerosene,the volume ratio of the aqueous-to-organic phase is 2:1,the extraction time is 30 min,and1 M sodium nitrite in 0.1 MHNO_(3).The theoretical stages require for the Co(Ⅱ) extraction are performed in the McCabe–Thiele diagram,and the extraction efficiency of Co(Ⅱ) reaches more than 99.00% after three-stage counter-current extraction with Co(Ⅱ) concentration of 2544mg/L.When the HCl concentration is 1.5 M,the volume ratio of the aqueous-to-organic phase is 1:1,the back-extraction efficiency of Co(Ⅱ)achieves 91.41%.After five extraction and back-extraction cycles,the Co(Ⅱ) extraction efficiency can still reach 93.89%.The Co(Ⅱ) extraction efficiency in the actual leaching solution reaches 100%. 展开更多
关键词 COBALT N263 sodium nitrite EXTRACTION iso-propyl alcohol spent lithium-ion battery
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Bone marrow-derived mesenchymal stem cells ameliorate sodium nitrite-induced hypoxic brain injury in a rat model 被引量:10
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作者 Elham H.A.Ali Omar A.Ahmed-Farid Amany A.E.Osman 《Neural Regeneration Research》 SCIE CAS CSCD 2017年第12期1990-1999,共10页
Sodium nitrite(Na NO2) is an inorganic salt used broadly in chemical industry. Na NO2 is highly reactive with hemoglobin causing hypoxia. Mesenchymal stem cells(MSCs) are capable of differentiating into a variety ... Sodium nitrite(Na NO2) is an inorganic salt used broadly in chemical industry. Na NO2 is highly reactive with hemoglobin causing hypoxia. Mesenchymal stem cells(MSCs) are capable of differentiating into a variety of tissue specific cells and MSC therapy is a potential method for improving brain functions. This work aims to investigate the possible therapeutic role of bone marrow-derived MSCs against Na NO2 induced hypoxic brain injury. Rats were divided into control group(treated for 3 or 6 weeks), hypoxic(HP) group(subcutaneous injection of 35 mg/kg Na NO2 for 3 weeks to induce hypoxic brain injury), HP recovery groups N-2 w R and N-3 w R(treated with the same dose of Na NO2 for 2 and 3 weeks respectively, followed by 4-week or 3-week self-recovery respectively), and MSCs treated groups N-2 w SC and N-3 w SC(treated with the same dose of Na NO2 for 2 and 3 weeks respectively, followed by one injection of 2 × 106 MSCs via the tail vein in combination with 4 week self-recovery or intravenous injection of Na NO2 for 1 week in combination with 3 week self-recovery). The levels of neurotransmitters(norepinephrine, dopamine, serotonin), energy substances(adenosine monophosphate, adenosine diphosphate, adenosine triphosphate), and oxidative stress markers(malondialdehyde, nitric oxide, 8-hydroxy-2′-deoxyguanosine, glutathione reduced form, and oxidized glutathione) in the frontal cortex and midbrain were measured using high performance liquid chromatography. At the same time, hematoxylin-eosin staining was performed to observe the pathological change of the injured brain tissue. Compared with HP group, pathological change of brain tissue was milder, the levels of malondialdehyde, nitric oxide, oxidized glutathione, 8-hydroxy-2′-deoxyguanosine, norepinephrine, serotonin, glutathione reduced form, and adenosine triphosphate in the frontal cortex and midbrain were significantly decreased, and glutathione reduced form/oxidized glutathione and adenosine monophosphate/adenosine triphosphate ratio were significantly increased in the MSCs treated groups. These findings suggest that bone marrow-derived MSCs exhibit neuroprotective effects against Na NO2-induced hypoxic brain injury through exerting anti-oxidative effects and providing energy to the brain. 展开更多
关键词 nerve regeneration HYPOXIA bone marrow-derived mesenchymal stem cells sodium nitrite monoamine neurotransmitter cell energy neural regeneration
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Reducing the Levels of Sodium, Saturated Animal Fat, and Nitrite in Dry-Cured Pork Meat Products: A Major Challenge 被引量:2
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作者 Hassan Safa Stéphane Portanguen Pierre-Sylvain Mirade 《Food and Nutrition Sciences》 2017年第4期419-443,共25页
The curing of meat is a conservation technique widely used since ancient times to prolong shelf-life. It consists in exposing meat to a mixture of sodium chloride and nitrate/nitrite. Sodium chloride affects the flavo... The curing of meat is a conservation technique widely used since ancient times to prolong shelf-life. It consists in exposing meat to a mixture of sodium chloride and nitrate/nitrite. Sodium chloride affects the flavor, texture and shelf-life of meat products. Animal fat mainly affects the flavor and texture, and nitrate and nitrite affect the color and flavor, and give cured meat products their typical aroma. Excessive intake of sodium has been linked to arterial hypertension and increased risk of cardiovascular diseases. Excessive intakes of saturated fatty acids in pork fat, and also of nitrite, have been identified as factors promoting some cancers. There is consequently an increasing consumer demand to reduce these ingredients in processed meat and so develop healthier cured meat products. This paper reviews how and to what extent sodium, animal fat rich in saturated fatty acids, and nitrite contents can be reduced in the production of dry-cured hams and dry-fermented sausages. 展开更多
关键词 sodium Saturated Fatty Acids nitrite Dry-Fermented SAUSAGE Dry-Cured HAM
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Selective oxidation of biomass derived 5-hydroxymethylfurfural to 2,5-diformylfuran using sodium nitrite 被引量:4
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作者 Xianxiang Liu Hui Ding +3 位作者 Qiong Xu Wenzhou Zhong Dulin Yin Shengpei Su 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2016年第1期117-121,共5页
A mild and simple process for the effective oxidation of 5-hydroxymethylfurfural(HMF) into 2,5-diformylfuran(DFF) has been developed using Na NO2 as the oxidant. Some important reaction parameters were investigate... A mild and simple process for the effective oxidation of 5-hydroxymethylfurfural(HMF) into 2,5-diformylfuran(DFF) has been developed using Na NO2 as the oxidant. Some important reaction parameters were investigated to optimize the oxidation of HMF into DFF. It was found that the reaction solvent was very crucial for this reaction. Trifluoroacetic acid was the best solvent for the oxidation of HMF into DFF by Na NO2.Under the optimal reaction condition, almost quantitative HMF conversion and high DFF yield of 90.4% were obtained after 1 h at room temperature. 展开更多
关键词 5-hydroxymethylfurfural 2 5-diformylfuran sodium nitrite Oxidation Renewable resource
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The Effect of Sodium Nitrite on Induction of Apoptosis in Human Gastric Adenocarcinoma Epithelia (AGS) Cells
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作者 Yanchao Liu Qiliang Qin +5 位作者 Agula Bo Hairong Zhang Qing Zhang Wenli Hao Yueling Hu Juan Sun 《Pharmacology & Pharmacy》 2015年第11期496-501,共6页
To examine the cytocidal effect of sodium nitrite on the cancer cell, we subjected human gastric adenocarcinoma epithelia (AGS) cells to various experimentation following exposure to sodium nitrite, and measured the r... To examine the cytocidal effect of sodium nitrite on the cancer cell, we subjected human gastric adenocarcinoma epithelia (AGS) cells to various experimentation following exposure to sodium nitrite, and measured the resulting changes in the levels of cell death, lactate dehydrogenase (LDH) release, and caspase-3, -6, -8, and -9 activities. Our data revealed that, in AGS cells, treatment with ≥6.25 mM sodium nitrite for 8 h resulted in an obvious increase in cell death. LDH release was also markedly increased following sodium nitrite treatment, but at a concentration of ≥6.25 mM for 24 h. This increasing trend showed a positive correlation (r = 0.9564, P < 0.05). In addition, we detected pronounced increases in caspase activities with various concentrations of sodium nitrite: caspase-3 at ≥25 mM for 1 h, ≥12.5 mM for 3 h and 6 h;caspase-9 at 50 mM for 1 h and 3 h, and ≥6.25 mM for 6 h;and caspase-6 at 50 mM for 1 h and 3 h. We did not however, detect any observable increase in the activity of caspase-8 following sodium nitrite treatment at any concentration or for any duration of treatment in this study. This data demonstrates that, in AGS cells, higher concentrations or longer durations of treatment with sodium nitrite could exhibit a cytocidal effect, and that sodium nitrite could induce apoptosis via activation of the caspase-9, caspase-3 cascade (intrinsic pathway) and caspase-6. 展开更多
关键词 sodium nitrite Human Gastric ADENOCARCINOMA EPITHELIA (AGS) CELLS APOPTOSIS
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Highly Sensitive Piezoelectric Response of Sodium Nitrite Nano-crystals to Low Applied Mechanical Pressures
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作者 H.Bishara S.Berger 《材料科学与工程(中英文A版)》 2018年第3期85-94,共10页
Development of highly-sensitive detectors of low mechanical pressures in the scale of few Pascal and below in environmental conditions are of a high technological demand for a variety of applications such as a remote ... Development of highly-sensitive detectors of low mechanical pressures in the scale of few Pascal and below in environmental conditions are of a high technological demand for a variety of applications such as a remote control of infants breathing and a leakage alert of hazardous gases.This paper reports on a highly sensitive piezoelectric detector of low applied mechanical pressures down to 0.1 Pa in atmospheric environment(10-4%pressure change).It is made of SN(sodium nitride)nanocrystals grown inside alumina pores with a preferred crystallographic orientation that can be controlled by their formation conditions based on a thermodynamic driving force.The SN nanocrystals inside the pores show a piezoelectric current response to low applied mechanical pressure which depends on the crystallographic orientation of the crystals and the level of residual or applied static strains.The piezoelectric current response is correlated with the unique molecular structure of the SN crystals. 展开更多
关键词 sodium nitrite crystal growth PIEZOELECTRIC pressure DETECTOR preferred crystallographic ORIENTATION
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Systematic pharmacology analysis of Sodium 8-(((carboxymethyl)amino)methyl)-4',7-bishydroxy-isoflavone-3'-sulfonate
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作者 Ze-Ping Luo Li-Wei Pan +1 位作者 Hai-Lin Chen Jun-Yu Lu 《Drug Combination Therapy》 2019年第4期186-198,共13页
The purpose of this study is to use the newly synthesized molecule Sodium 8-(((carboxymethyl)amino)methyl)-4',7-bishydroxy-isoflavone-3'-sulfonate(M)as a research object,the pharmacological mechanism of the mo... The purpose of this study is to use the newly synthesized molecule Sodium 8-(((carboxymethyl)amino)methyl)-4',7-bishydroxy-isoflavone-3'-sulfonate(M)as a research object,the pharmacological mechanism of the molecule was analyzed by using a series of Systematic pharmacology methods.The results show that the M molecule has a higher drug-like DL value of 0.59 and better molecular property parameters,namely Hdon=4,Hacc=10 and AlogP=0.94;A total of 11 M molecules related targets,namely F2,ESR1,AR,F10,CA2,DPP4,CCNA2,PRSS1,CDK2,GSK3B and PTPN1;A total of 140 diseases are associated with M molecule targets,and these diseases are mainly related to cancer and cardiovascular diseases;A total of 52 pathways involve the pharmacological mechanisms of M molecules,which are mainly related to cancer and other related diseases;GO-enriched analysis showed that these targets are closely related to the regulation of peptidase activity and biological processes such as blood coagulation and hemostasis.This article clearly demonstrated the pharmacological mechanism of M molecule,which provides references for exploring the pharmacological mechanism of new compounds. 展开更多
关键词 sodium 8-(((carboxymethyl)amino)methyl)-4' 7-bishydroxy-isoflavone-3'-sulfonate Systematic pharmacology analysis
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基于纳米银/聚L-谷氨酸修饰玻碳电极的电化学传感器用于泡菜中亚硝酸钠含量的测定
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作者 黄宝美 左岳瑶 +5 位作者 李媛 浦贤翠 贾悦 钟欣恒 余杰 代钰敏 《理化检验(化学分册)》 CAS CSCD 北大核心 2024年第5期502-506,共5页
采用电沉积和电聚合的方式,将纳米银和L-谷氨酸修饰在玻碳电极上,制得纳米银/聚L-谷氨酸修饰玻碳电极(Poly-L-Glu/Nano-Ag/GCE)。以0.2 mol·L^(-1)磷酸盐缓冲溶液(pH 7.0)为支持电解质,以Poly-L-Glu/Nano-Ag/GCE为工作电极,饱和甘... 采用电沉积和电聚合的方式,将纳米银和L-谷氨酸修饰在玻碳电极上,制得纳米银/聚L-谷氨酸修饰玻碳电极(Poly-L-Glu/Nano-Ag/GCE)。以0.2 mol·L^(-1)磷酸盐缓冲溶液(pH 7.0)为支持电解质,以Poly-L-Glu/Nano-Ag/GCE为工作电极,饱和甘汞电极为参比电极,铂电极为辅助电极,在最佳检测条件下,采用循环伏安法进行测定。结果表明:Poly-L-Glu/Nano-Ag/GCE对亚硝酸钠具有较好的选择性,亚硝酸钠的浓度在4.14×10^(-6)~1.35×10^(-3) mol·L^(-1)内与对应的氧化峰电流的绝对值呈线性关系,检出限(3s/k)为4.14×10^(-7) mol·L^(-1),并且该电极的制备方法具有较好的重复性。将PolyL-Glu/Nano-Ag/GCE用于泡菜样品中亚硝酸钠的测定,检出量为1.33×10^(-5) mol·L^(-1),加标回收率为98.9%~103%。 展开更多
关键词 纳米银 L-谷氨酸 亚硝酸钠 修饰电极 电化学传感器
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模拟胃液结合液质联用研究紫苏对内源性亚硝胺的阻断作用
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作者 喻凤香 陈煦 +1 位作者 陈祖武 曾思景 《中国果菜》 2024年第4期20-23,共4页
为研究蔬菜对亚硝胺的阻断效果,在模拟胃液环境下结合液质联用,研究紫苏提取液对内源性亚硝胺的阻断作用。结果表明,在模拟胃液环境下加入紫苏液与亚硝酸钠,亚硝酸钠清除率可达10.4%。加入紫苏液、亚硝酸钠和二乙胺进行液相色谱质谱检测... 为研究蔬菜对亚硝胺的阻断效果,在模拟胃液环境下结合液质联用,研究紫苏提取液对内源性亚硝胺的阻断作用。结果表明,在模拟胃液环境下加入紫苏液与亚硝酸钠,亚硝酸钠清除率可达10.4%。加入紫苏液、亚硝酸钠和二乙胺进行液相色谱质谱检测,空白样品和添加紫苏的样品中二乙基亚硝胺生成量分别为0.2、0.1 ng/mL,抑制率达到50%。添加紫苏的膳食中N-亚硝基二甲基(NDMA)、N-亚硝基二乙基(NDEA)、N-亚硝基二丁基(NDBA)、N-亚硝基吡咯烷(NPYR)含量显著降低。NDMA、NDEA在空白膳食中含量均为0.2 ng/g,紫苏试验组均未检出。NDBA空白对照为0.4 ng/g,紫苏试验组为0.2 ng/g,抑制率为50%;NPYR空白对照为8.6 ng/g,紫苏试验组为4.9 ng/g,抑制率为43%。因此,紫苏对内源性亚硝胺有明显的阻断作用。 展开更多
关键词 亚硝胺 紫苏 模拟胃液 液质联用 亚硝酸钠
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四种水溶性毒物中毒机理及检测方法研究进展
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作者 梁如柯 白旭 +2 位作者 辛国斌 张高勤 朱军 《刑事技术》 2024年第2期171-176,共6页
水溶性毒物是指在水中具有较高溶解度的毒物,一般具有吸收迅速及毒性较高的特点,极易通过血液循环分布到体内各器官组织,从而对人体造成危害。本文选择氰化物、亚硝酸盐、氟乙酸钠和硼砂四种常见水溶性毒物,对其理化性质、毒理机制、中... 水溶性毒物是指在水中具有较高溶解度的毒物,一般具有吸收迅速及毒性较高的特点,极易通过血液循环分布到体内各器官组织,从而对人体造成危害。本文选择氰化物、亚硝酸盐、氟乙酸钠和硼砂四种常见水溶性毒物,对其理化性质、毒理机制、中毒症状、体内代谢过程及国内外检测技术发展现状和未来趋势进行综述,希望为法庭科学水溶性毒物检验鉴定和中毒死亡案件原因调查提供参考。 展开更多
关键词 法医毒物学 亚硝酸盐 氰化物 氟乙酸钠 硼砂 水溶性毒物
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复方参及合剂对小鼠抗缺氧及疲劳的作用研究
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作者 李萌 阿丽古丽·买买提依明 +4 位作者 李建瑛 李叶 李倩 王瑞 尹东锋 《中国药业》 CAS 2024年第8期44-48,共5页
目的探讨复方参及合剂对小鼠抗缺氧及疲劳的作用。方法采用常压密闭缺氧实验、亚硝酸钠中毒实验检测小鼠抗缺氧能力,记录小鼠存活时间及小鼠脑、心肌组织中超氧化物歧化酶(SOD)、丙二醛(MDA)、谷胱甘肽过氧化物酶(GSH-Px)水平;采用负重... 目的探讨复方参及合剂对小鼠抗缺氧及疲劳的作用。方法采用常压密闭缺氧实验、亚硝酸钠中毒实验检测小鼠抗缺氧能力,记录小鼠存活时间及小鼠脑、心肌组织中超氧化物歧化酶(SOD)、丙二醛(MDA)、谷胱甘肽过氧化物酶(GSH-Px)水平;采用负重游泳实验检测小鼠耐疲劳能力,记录小鼠力竭游泳时间,同时检测血清中三磷酸腺苷(ATP)、尿素氮(BUN)、肌糖原(MG)、肝糖原(Gly)、乳酸(LA)、乳酸脱氢酶(LDH)水平。3个实验均取KM小鼠50只,随机分为空白对照组(等体积生理盐水),阳性对照组(红景天胶囊0.3 g/kg),复方参及合剂低、中、高剂量组(简称低、中、高剂量组;1.0,2.0,3.0 g/kg),各组小鼠灌胃等体积生理盐水或相应药物(10 mL/kg),每日1次,连续14 d。结果与空白对照组比较,阳性对照组及低、中、高剂量组小鼠常压密闭缺氧条件下存活时间均显著延长(P<0.05);脑组织中,高剂量组SOD,低、中、高剂量组GSH-Px水平均显著升高,阳性对照组及低、中、高剂量组MDA水平均显著降低;心肌组织中,高剂量组SOD水平,阳性对照组及低、中、高剂量组GSH-Px水平均显著升高,低、高剂量组MDA水平均显著降低(P<0.05)。与空白对照组比较,阳性对照组及低、中、高剂量组小鼠亚硝酸钠中毒条件下存活时间均显著延长(P<0.05);脑组织中,低、中剂量组SOD,中、高剂量组GSH-Px水平均显著升高;心肌组织中,阳性对照组及中剂量组SOD,中剂量组GSH-Px水平均显著升高,阳性对照组及低、中、高剂量组MDA水平均显著降低(P<0.05)。与空白对照组比较,低、中、高剂量组小鼠负重游泳力竭时间均显著延长;血清中,高剂量组小鼠ATP,低、中、高剂量组LDH,中剂量组Gly水平均显著升高,阳性对照组及低、中、高剂量组BUN和LA水平均显著降低(P<0.05)。结论复方参及合剂可对小鼠发挥抗缺氧及疲劳作用。 展开更多
关键词 抗缺氧 耐疲劳 复方参及合剂 小鼠 常压密闭缺氧实验 亚硝酸钠中毒实验 负重游泳实验
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离子色谱-质谱法检测五种水溶性毒物
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作者 梁如柯 白旭 +3 位作者 张高勤 辛国斌 卫娟娜 朱军 《实验与分析》 2024年第2期37-40,共4页
为建立一种离子色谱-质谱法检测血液中γ-羟基丁酸(GHB)、氟乙酸钠、亚硝酸钠、草甘膦和草铵膦五种水溶性毒物的方法,选用AS19阴离子色谱柱进行分离,以在线产生的50 mmol/L氢氧化钠为淋洗液等度淋洗,飞行时间质谱仪作检测器,采用电喷雾... 为建立一种离子色谱-质谱法检测血液中γ-羟基丁酸(GHB)、氟乙酸钠、亚硝酸钠、草甘膦和草铵膦五种水溶性毒物的方法,选用AS19阴离子色谱柱进行分离,以在线产生的50 mmol/L氢氧化钠为淋洗液等度淋洗,飞行时间质谱仪作检测器,采用电喷雾电离源负离子模式、选择离子监测模式(Selected Ion Monitor,SIM)进行分析,外标法定量。利用离子色谱-质谱法检测五种水溶性毒物简单快速、专属性强、灵敏度高,可为司法鉴定实践提供重要的科学支撑。 展开更多
关键词 离子色谱-质谱联用 Γ-羟基丁酸 氟乙酸钠 亚硝酸钠 草甘膦 草铵膦 检验
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亚硝酸钠拜师记
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作者 李想 王太宝 +1 位作者 吕萍 丁寒锋 《大学化学》 CAS 2023年第7期32-37,共6页
食品防腐剂的出现极大地延长了食品保存的时间,在现代食品工业中占有重要地位。随着生活水平的提高,人们越来越关心食品安全问题,但仍然存在不少误区。本文以拟人化的手法,介绍了几类食品防腐剂的作用原理和利弊,旨在向大众普及科学的... 食品防腐剂的出现极大地延长了食品保存的时间,在现代食品工业中占有重要地位。随着生活水平的提高,人们越来越关心食品安全问题,但仍然存在不少误区。本文以拟人化的手法,介绍了几类食品防腐剂的作用原理和利弊,旨在向大众普及科学的防腐剂知识。 展开更多
关键词 亚硝酸钠 防腐剂 苯甲酸钠
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川芎治疗偏头痛药理机制研究进展 被引量:4
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作者 柴金秀 张禹 +1 位作者 吕永旭 徐冰 《辽宁中医药大学学报》 CAS 2023年第5期102-106,共5页
偏头痛在中国是一种常见的搏动性、原发性的头痛病,多一侧起病,重者可致残,对患者的生活质量产生重大影响,是目前治疗的一大难点。中医治疗偏头痛既可以改善疾病的症状,还可以祛除疾病的根源,具有多目标、多途径的特点。通过对治疗偏头... 偏头痛在中国是一种常见的搏动性、原发性的头痛病,多一侧起病,重者可致残,对患者的生活质量产生重大影响,是目前治疗的一大难点。中医治疗偏头痛既可以改善疾病的症状,还可以祛除疾病的根源,具有多目标、多途径的特点。通过对治疗偏头痛的古今医案数据进行分析,发现中医治疗主要采取祛瘀、平肝阳、补虚三种治疗策略。其中化瘀方中大多含有川芎,发现川芎可以活血化瘀,改善血液流变学性质,镇静,镇痛,清除氧自由基,同时也发现含有川芎的药对居于偏头痛治疗使用药对之首。川芎是临床上治疗头痛、血管性头痛、偏头痛用药频率最高的单味中药之一。该文对川芎治疗偏头痛的药理作用机制进行综述,为川芎临床治疗和预防偏头痛提供理论科学依据。并对川芎的有效成分现代研究进行归纳梳理。结果发现川芎治疗偏头痛的药理机制包括抑制氧自由基活性,减轻炎症反应;抗神经元凋亡,保护脑神经;调节神经递质,降低痛阈值;抗血小板聚集;调肠道菌群等。 展开更多
关键词 偏头痛 川芎 川芎嗪 阿魏酸钠 藁本内酯 药理机制
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番茄青枯病拮抗菌株B-6的诱变选育 被引量:1
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作者 李甜爽 王潞伟 +2 位作者 任潇妍 刘海霞 王美琴 《山西农业科学》 2023年第7期810-816,共7页
青枯病是由青枯劳尔氏菌(Ralstonia solanacearum)侵染引起,是设施番茄生产上一类重要的土传性病害,给种植户造成巨大的经济损失。筛选高效突变生防菌株成为目前青枯病防控的重要手段之一。为了给生防菌剂的进一步开发应用提供依据,研... 青枯病是由青枯劳尔氏菌(Ralstonia solanacearum)侵染引起,是设施番茄生产上一类重要的土传性病害,给种植户造成巨大的经济损失。筛选高效突变生防菌株成为目前青枯病防控的重要手段之一。为了给生防菌剂的进一步开发应用提供依据,研究以筛选出具有抑菌活性的铜绿假单胞菌(Pseudomonas aeruginosa)B-6为出发菌株,采用紫外线和亚硝酸钠复合诱变处理,计算致死率和正突变率确定最佳诱变条件,利用平板初筛和摇瓶发酵复筛获得高效突变菌株,测定高效突变菌株抑菌活性的遗传稳定性,并与出发菌株进行生长曲线的对比。结果表明,在紫外照射时长为3 min和亚硝酸钠浓度为0.045 mol/L复合诱变条件下,获得1株抑菌活性最强的高效突变菌株UH-9;该菌株对番茄青枯病菌抑菌圈平均直径达到28.6 mm,抑菌活性与出发菌株相比提高了86.5%,菌株在传代培养7次后抑菌活性无显著变化,具有良好的遗传稳定性。复合诱变处理比单一紫外诱变处理及亚硝酸钠诱变处理抑菌活性分别提高39.1%和25.4%,复合诱变比单一诱变抑菌活性更好。通过对比菌株UH-9和B-6的生长曲线可知,生长时期相同,且13 h后UH-9的OD600高于B-6。 展开更多
关键词 番茄青枯病 铜绿假单胞菌 高效突变菌株UH-9 紫外诱变 亚硝酸钠诱变
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考虑转化率的亚硝酸钠与氯化铵体系反应动力学
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作者 战永平 罗明良 +1 位作者 付春丽 刘纪康 《中国石油大学学报(自然科学版)》 EI CAS CSCD 北大核心 2023年第3期173-180,共8页
针对现有未考虑反应物转化率的NaNO_(2)/NH_(4)Cl反应动力学方程难以有效预测生热/生氮气情况的问题,运用实验测试分析方法探究氮气生成反应的H^(+)浓度界限、反应转化率及其变化规律;采用灰色关联分析法研究各因素的影响程度;利用牛顿... 针对现有未考虑反应物转化率的NaNO_(2)/NH_(4)Cl反应动力学方程难以有效预测生热/生氮气情况的问题,运用实验测试分析方法探究氮气生成反应的H^(+)浓度界限、反应转化率及其变化规律;采用灰色关联分析法研究各因素的影响程度;利用牛顿-拉斐逊迭代方法计算引入反应转化率的反应动力学参数,探讨生热/生氮气反应的预测方法。结果表明:NaNO_(2)/NH_(4)Cl体系氮气生成反应的H^(+)浓度界限为c_(H^(+))≤0.0225 mol/L(或pH≥1.65),且氮气生成反应转化率随着反应物和H^(+)浓度的增大,温度的升高而增大,其关联性最高的反应物浓度的关联度为0.8;考虑反应转化率的NaNO_(2)/NH_(4)Cl体系反应动力学方程为dηd t=4.74×10^(4)e^(-3389/T)c^(1.545)_(H^(+))c^(1.346)c_(0)(1-η)2.346或(1-η)^(-1.346)-1/1.346=4.74×10^(4)e^(-3389/T)c^(1.545)_(H^(+))c^(1.346)0_t,η<1,可有效、便捷地进行生热/生氮气反应预测。 展开更多
关键词 NaNO_(2)/NH4Cl体系 H+浓度界限 转化率 反应动力学方程
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Toxicity detection of sodium nitrite,borax and aluminum potassium sulfate using electrochemical method 被引量:9
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作者 Dengbin Yu Daming Yong Shaojun Dong 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2013年第4期785-790,共6页
Based on the inhibition effect on the respiratory chain activity of microorganisms by toxicants, an electrochemical method has been developed to measure the current variation of a mediator in the presence of microorga... Based on the inhibition effect on the respiratory chain activity of microorganisms by toxicants, an electrochemical method has been developed to measure the current variation of a mediator in the presence of microorganisms contacted with a toxicant. Microelectrode arrays were adopted in this study, which can accelerate the mass transfer rate of an anaiyte to the electrode and also increase the total current signal, resulting in an improvement in detection sensitivity. We selected Escherichia coli as the testee and the standard glucose- glutamic acid as an exogenous material. Under oxygen restriction, the experiments in the presence of toxicant were performed at optimum conditions (solution pH 7.0, 37℃ and reaction for 3 hr). The resulting solution was then separated from the suspended microorganisms and was measured by an electrochemical method, using ferricyanide as a mediator. The current signal obtained represents the reoxidation of ferrocyanide, which was transformed to inhibiting efficiency, IC50, as a quantitative measure of toxicity. The IC50 values measured were 410, 570 and 830 mg/L for sodium nitrite, borax and aluminum potassium sulfate, respectively. The results show that the toxicity sequence for these three food additives is consistent with the value reported by other methods. Furthermore, the order of damage degree to the microorganism was also observed to be: sodium nitrite 〉 borax 〉 aluminum potassium sulfate 〉 blank, according to the atomic force microscopy images of E. coli after being incubated for 3 hr with the toxic compound in buffer solutions. The electrochemical method is expected to be a sensitive and simple alternative to toxicity screening for chemical food additives. 展开更多
关键词 food additives sodium nitrite BORAX aluminum potassium sulfate microelectrode arrays
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不同碳源对反硝化过程中亚硝酸盐积累的影响
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作者 王义英 李玲玲 《青岛科技大学学报(自然科学版)》 CAS 2023年第1期35-43,共9页
采用葡萄糖和乙酸钠对反硝化污泥进行200 d的驯化培养后,通过批次试验研究不同碳源对反硝化过程中亚硝酸盐积累的影响。研究结果表明:采用葡萄糖培养的反硝化污泥以葡萄糖为碳源,反硝化过程中亚硝酸盐积累浓度较低;n(C)/n(N)为5时,NO_(2... 采用葡萄糖和乙酸钠对反硝化污泥进行200 d的驯化培养后,通过批次试验研究不同碳源对反硝化过程中亚硝酸盐积累的影响。研究结果表明:采用葡萄糖培养的反硝化污泥以葡萄糖为碳源,反硝化过程中亚硝酸盐积累浓度较低;n(C)/n(N)为5时,NO_(2)^(-)-N最大积累浓度仅为13.79 mg·L^(-1),最大NO_(2)^(-)-N积累率为31.20%。采用乙酸钠培养的反硝化污泥以乙酸钠为碳源,反硝化过程中亚硝酸盐能快速积累,且积累浓度较高;n(C)/n(N)为3,反应至120 min时NO_(2)^(-)-N积累浓度为37.86 mg·L^(-1),NO_(2)^(-)-N积累率达到72.48%;该污泥以葡萄糖为碳源,反硝化过程中亚硝酸盐积累浓度也较高;n(C)/n(N)为3,反应至240 min时,NO_(2)^(-)-N积累浓度为24.41 mg·L^(-1),最大NO_(2)^(-)-N积累率达到52.59%。采用葡萄糖和乙酸钠培养的反硝化污泥中均以Thauera为优势属,Thauera相对丰度分别为58.69%和70.62%。 展开更多
关键词 葡萄糖 乙酸钠 反硝化 亚硝酸盐积累 菌群结构
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亚硫酸钠-柠檬酸钾体系络合剂对镀金层性能的影响
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作者 付银辉 李元朴 董东 《表面技术》 EI CAS CSCD 北大核心 2023年第4期390-398,共9页
目的 研究亚硫酸钠-柠檬酸钾体系络合剂对可伐基板镀金层共晶焊接性能的影响机理,从而优化络合剂含量工艺范围,提升镀金层金锗共晶可焊性。方法 采用扫描电子显微镜及能谱仪(SEM-EDS)、X射线衍射仪(XRD)、极化曲线等分析方法,结合镀金... 目的 研究亚硫酸钠-柠檬酸钾体系络合剂对可伐基板镀金层共晶焊接性能的影响机理,从而优化络合剂含量工艺范围,提升镀金层金锗共晶可焊性。方法 采用扫描电子显微镜及能谱仪(SEM-EDS)、X射线衍射仪(XRD)、极化曲线等分析方法,结合镀金层孔隙、金锗共晶焊接润湿性和剪切强度测试,研究了亚硫酸钠-柠檬酸钾体系络合剂,对镀金层表面金锗焊料润湿性,金锗共晶层结合力、表面和截面形貌、结晶状态、孔隙,以及金锗共晶焊接界面微观形貌等的影响。结果 亚硫酸钠和柠檬酸钾均能起到络合剂作用,当络合剂亚硫酸钠质量浓度为120~160 g/L和柠檬酸钾质量浓度为40~60 g/L时,络合剂含量的增加可使镀金液阴极过电位明显增大,从而使所制备的镀金层结晶更加致密。当络合剂亚硫酸钠质量浓度为160~200 g/L、柠檬酸钾质量浓度为60~100g/L时,电沉积的镀金层表面明显平整,截面形貌致密,孔隙少,且以(311)晶面择优生长,晶粒尺寸为43.7nm,晶面间距为0.123nm,金锗焊料润湿良好,金锗共晶层结合力较大,剪切强度可达3 MPa以上,可满足金锗共晶焊接使用要求。结论 亚硫酸钠-柠檬酸钾体系络合剂含量对镀金层的结晶状态和致密性影响明显,镀金层结晶状态和致密性与其表面金锗共晶可焊性有直接关系,镀金层越结晶致密越有利于其表面共晶焊接质量,通过控制亚硫酸钠-柠檬酸钾络合剂含量可有效提高镀金层表面金锗共晶焊接质量。 展开更多
关键词 亚硫酸钠-柠檬酸钾 无氰镀金液 络合剂 镀金层 金锗共晶焊接
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钠-葡萄糖协同转运蛋白-2抑制剂心肾保护作用机制的网络药理学研究
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作者 巴文强 李艳 +1 位作者 朱文山 李梦媛 《中国当代医药》 CAS 2023年第10期18-21,F0003,F0004,共6页
目的基于网络药理学研究钠-葡萄糖协同转运蛋白-2抑制剂(SGLT-2i)心肾保护的作用机制。方法通过相关数据库搜索SGLT-2i与疾病相关的靶点,应用STRING 11.5数据库构建蛋白质-蛋白质相互作用(PPI)网络,使用CytoHubba插件得到关键靶点,利用M... 目的基于网络药理学研究钠-葡萄糖协同转运蛋白-2抑制剂(SGLT-2i)心肾保护的作用机制。方法通过相关数据库搜索SGLT-2i与疾病相关的靶点,应用STRING 11.5数据库构建蛋白质-蛋白质相互作用(PPI)网络,使用CytoHubba插件得到关键靶点,利用Metascape数据库进行基因本体(GO)和京都基因与基因组百科全书(KEGG)富集分析,利用CB-Dock平台进行分子对接。结果共预测SGLT-2i靶点450个,获得疾病靶点1221个,交集靶点54个,关键靶点为丝裂原活化蛋白激酶1(MAPK1)、表皮生长因子受体(EGFR)、RAC-α丝氨酸/苏氨酸蛋白激酶(AKT1)等。KEGG结果显示,关键通路可能是糖尿病并发症中的晚期糖基化终产物-糖基化终产物受体信号通路、酪氨酸蛋白激酶-信号转导和转录激活因子信号通路等。分子对接显示,SGLT-2i与关键靶点结合能力较好。结论本研究初步推测了SGLT-2i多靶点、多通路的心肾保护作用机制,这为该类药物心肾保护机制提供了新的认识。 展开更多
关键词 钠-葡萄糖协同转运蛋白-2抑制剂 心肾保护 网络药理学 分子对接 作用机制
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