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1.
一种新型絮凝剂对养殖水体中铜的去除作用   总被引:2,自引:0,他引:2  
利用蒙脱石与壳聚糖2种天然材料,将壳聚糖固载于蒙脱石表面作为絮凝剂,用于处理养殖水体中重金属铜。试验结果表明,在蒙脱石负载壳聚糖投加量为0.8‰~1.0‰、絮凝吸附反应时间为16 min、溶液pH值为6时,对铜的去除效果最佳;与单一材料相比较,制备的新型絮凝剂对铜的去除能力强,且用量少。  相似文献   

2.
铜和邻苯二胺在水相中和矿物上交互作用的研究   总被引:4,自引:0,他引:4  
采用室内分析测定方法,研究了铜和邻苯二胺在水相以及高岭石和蒙脱石上的交互作用过程。结果表明,在纯水体系中邻苯二胺与铜发生了明显的络合反应,通过等摩尔法推导得出邻苯二胺与铜的络合系数为2,表观络合常数约在10^7数量级,且随酸度的变化而改变;邻苯二胺的存在降低了铜在高岭石上的吸附量;而在蒙脱石体系中,邻苯二胺的存在则增加了铜的吸附量,并随邻苯二胺浓度的增加这种作用更加明显。与此同时,邻苯二胺均降低了游离态铜在平衡溶液中的含量,而且铜的存在也相应降低了溶液中游离态邻苯二胺的浓度。该研究对于深入理解复杂体系中复合污染物之间交互作用过程具有一定的参考意义。  相似文献   

3.
姜璋  霍淑慧  袁莉 《安徽农业科学》2008,36(8):3077-3079
研究了3,6-双(4-溴-2磺基-苯偶氮)-4,5-二羟基-2,7-萘二磺酸(溴代磺酸偶氮Ⅲ)与铜的显色反应。结果表明,Cu(Ⅱ)与溴代磺酸偶氮Ⅲ形成了蓝色络合物,络合比为1∶1,该络合物最大吸收波长在616.8nm处,表观摩尔吸光系数ε=3.3×105L(/mol·cm),Cu(Ⅱ)在0-1.024μg/ml范围内符合比尔定律,检出限(3σ)为7.03×10-4μg/m(ln=20),相对标准偏差(RSD)是0.56%-4.68%。利用该法检测水果、蔬菜和茶叶中的铜,操作简便,灵敏度高。  相似文献   

4.
Device-quality copper and nickel films were deposited onto planar and etched silicon substrates by the reduction of soluble organometallic compounds with hydrogen in a supercritical carbon dioxide solution. Exceptional step coverage on complex surfaces and complete filling of high-aspect-ratio features of less than 100 nanometers width were achieved. Nickel was deposited at 60 degrees C by the reduction of bis(cyclopentadienyl)nickel and copper was deposited from either copper(I) or copper(II) compounds onto the native oxide of silicon or metal nitrides with seed layers at temperatures up to 200 degrees C and directly on each surface at temperatures above 250 degrees C. The latter approach provides a single-step means for achieving high-aspect-ratio feature fill necessary for copper interconnect structures in future generations of integrated circuits.  相似文献   

5.
The binuclear copper enzyme tyrosinase activates O2 to form a mu-eta2:eta2-peroxodicopper(II) complex, which oxidizes phenols to catechols. Here, a synthetic mu-eta2:eta2-peroxodicopper(II) complex, with an absorption spectrum similar to that of the enzymatic active oxidant, is reported to rapidly hydroxylate phenolates at -80 degrees C. Upon phenolate addition at extreme temperature in solution (-120 degrees C), a reactive intermediate consistent with a bis-mu-oxodicopper(III)-phenolate complex, with the O-O bond fully cleaved, is observed experimentally. The subsequent hydroxylation step has the hallmarks of an electrophilic aromatic substitution mechanism, similar to tyrosinase. Overall, the evidence for sequential O-O bond cleavage and C-O bond formation in this synthetic complex suggests an alternative intimate mechanism to the concerted or late stage O-O bond scission generally accepted for the phenol hydroxylation reaction performed by tyrosinase.  相似文献   

6.
为研究铜(Ⅱ)-多酚纳米复合物对水培营养液中藻类生长的抑制作用及对生菜的影响,将金属离子(Cu2+)和天然植物多酚(杨梅单宁BT、橡椀单宁VT、塔拉单宁Tr、单宁酸TA)自组装形成铜(Ⅱ)-多酚纳米复合物,设置铜(Ⅱ)-多酚纳米复合物抑制小球藻试验和实际水培生菜试验。结果表明:1)多酚诱导的界面相互作用促使铜(Ⅱ)-多酚纳米复合物能够黏附于藻类细胞表面并缓慢释放铜离子,从而引起了藻细胞的氧化损伤和藻细胞的死亡,可实现长期有效的抑藻效果。其中,铜与杨梅单宁BT形成的Cu-BT使用7 d后,对小球藻的抑制率仍然可达到99%。2) Cu2+与缩合类植物多酚(杨梅单宁BT、橡椀单宁VT)自组装形成的Cu-BT和Cu-VT对藻类生长的抑制能力优于Cu2+与水解类植物多酚(塔拉单宁Tr、单宁酸TA)自组装形成的Cu-Tr和Cu-TA。3)铜(Ⅱ)-多酚纳米复合物能够在实际生产中抑制营养液中藻类的生长,并且与对照相比...  相似文献   

7.
研 究了土壤中有机 矿质复合胶体的金 属离子平衡,结 果显示:在含 Ca2 + , Fe3 + , Al3 + 的溶 液中,高岭石胡敏酸复合体较蒙脱石胡敏酸复合体吸附较多的 Fe3+ ,而吸附的 Ca2 + 和 Al3 + 则较少;蒙脱石胡敏酸复合体在含 Fe3 + , Al3 + 的溶 液中,释出的 Ca2+ 较多⒚这些离 子平衡与溶液 p H 条件有 关,在高岭类复合体中,p H 的影响更为明显⒚  相似文献   

8.
改性蒙脱石修复镉污染对水稻根际土壤酶活性的影响   总被引:1,自引:0,他引:1  
为探讨钝化修复重金属Cd污染土壤中改性蒙脱石的使用对水稻根际与非根际土壤Cd活性、酶活性等的影响,采用盆栽试验通过袋式根际箱装置种植水稻,并对土壤施加巯基-蒙脱石复合材料、蒙脱复合调理剂材料及巯基复合材料。结果表明:3种材料以0.5%的量施入后,糙米Cd浓度分别降低43.6%、25.9%和36.0%;Cd有效态浓度在根际土壤中分别降低55.3%、12.0%和35.2%,在非根际土壤中分别降低54.9%、9.76%和35.4%。蒙脱复合调理剂材料能提高土壤中过氧化氢酶、脲酶活性,巯基复合材料能提高土壤中脲酶活性,巯基-蒙脱石复合材料能提高非根际土壤中蔗糖酶活性。施加修复材料后,水稻根际土壤磷酸酶活性显著高于非根际土壤。研究表明,这3种改性蒙脱石钝化材料降低了Cd在根际土壤中的活性,有效地固定了土壤中的Cd,降低了水稻对镉的吸收,同时提高了土壤酶的活性,改善了Cd污染的水稻根际土壤环境质量。  相似文献   

9.
Femtomole amounts of racemic mixtures of derivatized amino acids were resolved and analyzed rapidly in about 10 minutes by means of high-voltage zone electrophoresis with laser-fluorescence detection. The electrophoresis was performed in capillary columns containing a chiral support electrolyte. A number of dansyl amino acids were resolved by the diastereomeric interaction between the DL-amino acid and the copper(II) complex of L-histidine present in the support electrolyte. A combination of electro-osmotic and electrophoretic action caused all species, positively charged, neutral, and negatively charged, to pass through the 0.5- nanoliter detection volume where they were subjected to laser excitation.  相似文献   

10.
本文报道2—(5—硝基—2—吡啶偶氮)—5—二甲氨基苯甲酸(5—NO_2—PAMB)分光光度法测定微量铜。试剂与铜离子反应迅速,水溶性很好。配合物的表观摩尔吸光系数为8.04×10~4L.mol~(-1).cm~(-1)。络合比Cu:5—NO_2—PAMB=1:2,Cu~(2+)浓度在O~35μg/25mL范围内服从比耳定律。方法用于测定铝合金标样及金属铝中的铜,结果与标准值相符。标准加入回收率在99%~102%之间。  相似文献   

11.
在室温条件下通过固相反应合成了异烟酸铜配合物,考察了铜源、反应时间、原料配比对合成产物的影响.结果表明,最佳合成工艺条件为:以醋酸铜为铜源,反应时间为2 h,醋酸铜∶异烟酸=1∶2(摩尔比).采用元素分析、红外光谱、紫外光谱以及X-射线粉末衍射光谱对所合成的配合物进行了表征.抑菌活性实验表明,该配合物对金黄色葡萄球菌、枯草芽孢杆菌、大肠杆菌、铜绿假单胞菌、嗜水气单胞菌和耶尔森氏菌具有一定的抑菌活性.  相似文献   

12.
研究了牙鲆Paralichthysolivaceus内脏、肌肉、鳃组织对海水中Cu的吸收、积累和排放规律,以及海水中总有机碳(TOC)浓度和不同种类配体对Cu吸收的影响。试验结果表明,当Cu浓度为0 5mg/L时,各组织内Cu蓄积量随暴露时间的增加而增大,第13d均达到吸收平衡,各组织Cu蓄积量为内脏(971 89mg/kg干重)>肌肉(204 99mg/kg干重)>鳃(90 04mg/kg干重)。试验进行13d后,将牙鲆移入清洁海水中排放,结果表明,随着排放时间的增加,各组织Cu蓄积量下降,第8d接近排放平衡,各组织Cu排出率为肌肉(89%)>鳃(86 5%)>内脏(83 7%)。海水中TOC浓度及不同种类的配体对牙鲆吸收、蓄积Cu有明显影响,当TOC浓度相同时,孔石莼Ulvapertusa分泌物比牙鲆分泌物更能降低Cu的生物有效性;当配体相同时,随着TOC浓度的升高,各组织Cu蓄积量均明显下降,表明海水中TOC能降低Cu的生物有效性;海水中Cu2+的表观络合容量(ACu)随着TOC浓度的增加有明显上升趋势,并与TOC浓度呈线性相关。  相似文献   

13.
The three-dimensional crystal structure of the copper-containing nitrite reductase (NIR) from Achromobacter cycloclastes has been determined to 2.3 angstrom (A) resolution by isomorphous replacement. The monomer has two Greek key beta-barrel domains similar to that of plastocyanin and contains two copper sites. The enzyme is a trimer both in the crystal and in solution. The two copper atoms in the monomer comprise one type I copper site (Cu-I; two His, one Cys, and one Met ligands) and one putative type II copper site (Cu-II; three His and one solvent ligands). Although ligated by adjacent amino acids Cu-I and Cu-II are approximately 12.5 A apart. Cu-II is bound with nearly perfect tetrahedral geometry by residues not within a single monomer, but from each of two monomers of the trimer. The Cu-II site is at the bottom of a 12 A deep solvent channel and is the site to which the substrate (NO2-) binds, as evidenced by difference density maps of substrate-soaked and native crystals.  相似文献   

14.
Chicken manure with similar content of copper and zinc was changes of organic carbon and humus substance complexed chosen to conduct a composting experiment to investigate the copper (HS-Cu) and zinc (HS-Zn), which were extracted by water (H2O), sodium hydroxide (NaOH), and sodium pyrophate-NaOH mixture (Na4P2O7-NaOH), sequentially. Distributions of copper and zinc in fulvic acids (FA) and humic acids (HA) in the three extracts were studied. During manure composting, the concentrations of copper and zinc increased from about 500 mg kg^-1 in the raw material to 1 100 mg kg^-1 in the final products. HS-Cu in H2O, NaOH, and Na4P2O7-NaOH extracts occupied 6.7, 26.7, and 19% averagely of total copper and HS-Zn represented 2.7, 13.7, and 17% averagely of total zinc in compost, respectively. In water extracts, both HA and FA mainly complexed with Cu and the mole ratio of Cu to Zn was 2.8 in HA fractions and was 2.6 in FA fractions, respectively. HA mainly complexed with copper, so that the ratios of HA-Cu to HA-Zn averaged 3.4 in NaOH extracts. FA had a similar potential to complex with copper and zinc, so that the ratio of FA-Cu to FA-Zn was close to 1. In Na4P2O7-NaOH extracts, HA or FA had a similar potential to complex with copper and zinc. The ratio of HS-Cu to HS-Zn was close to 1. With manure composting, Na4P2O7-NaOH extractable HS-Zn increased to a level as high as HS-Cu. This indicated that more and more stable complexes of HS-Zn were formed in the late decomposition period. The competition between copper and zinc to be complexed with humic substance became weaker and weaker with the decomposition process.  相似文献   

15.
刘静静  陈天虎  彭书传 《安徽农业科学》2011,39(35):21935-21936,21939
[目的]探索纯蒙脱石处理含锌废水的因素与效果。[方法]从蒙脱石提纯入手,进行纯蒙脱石处理含锌废水的试验研究,探讨纯蒙脱石对含锌废水处理效果的影响因素,确定纯蒙脱石去除水中Zn2+的工艺条件,并研究纯蒙脱石对Zn2+的吸附等温曲线。[结果]纯蒙脱石对含锌废水处理效果主要受振荡速度、吸附时间、溶液pH值和投加量等因素影响。温度为30℃时纯蒙脱石对Zn2+的吸附等温曲线更符合Langmuir方程和BET方程,相关系数均为0.986 9,最大吸附容量39.00 mg/g。在该试验条件下,纯蒙脱石对水中Zn2+(20ml,Zn2+浓度均为50 mg/L)达到最佳去除效果时的工艺条件为:振荡速度150 r/min,吸附时间60 min,溶液pH值6.10,此条件下Zn2+去除率达到85.3%。[结论]该研究为应用蒙脱石开发污水处理新材料提供了科学依据。  相似文献   

16.
添加蒙脱石对猪粪好氧堆肥腐熟度和重金属钝化的影响   总被引:1,自引:0,他引:1  
为进一步提升猪粪堆肥品质,以猪粪和秸秆为原料,以蒙脱石为调理剂进行强制通风好氧堆肥,分析堆肥过程中温度、pH、含水率、电导率、种子发芽指数和重金属形态的变化,研究添加蒙脱石对猪粪堆肥腐熟度和重金属钝化效果的影响。结果表明,添加蒙脱石可提高猪粪好氧堆肥温度,延长高温期,有效促进堆肥腐熟,提升堆肥品质。当蒙脱石添加量为猪类干质量的5%时,堆肥的种子发芽指数可达92%,堆肥效果最好。添加适量蒙脱石可提高堆肥的重金属钝化效果。当蒙脱石添加量为猪类干质量的5%时,对可交换态Cu和Zn的钝化效果最佳,分别达到23.7%和17.2%。  相似文献   

17.
[目的]研究Schiff碱抑菌活性的影响因素,为寻找理想的抗癌、抑菌药物提供参考。[方法]合成5种5-溴水杨醛氨基酸Schiff碱配体,并分别与铜(II)形成配合物。采用红外光谱、紫外光谱进行表征,并分别进行抑菌试验。[结果]从红外光谱数据及紫外光谱数据中可以看出,5-Br-Sal与AA完全反应生成了Schiff碱配体,该类配体与铜(II)形成配合物时,C-O中的氧原子以及C=N中的氮原子参与了对铜(II)的配位作用;同Sal-AASchiff碱相比,5-Br-Sal-AASchiff碱E2带、B带、R带均发生了红移,从紫外光谱图中可以看出,配合物的吸收峰位置相对于配体而言均发生了蓝移。从抑菌试验结果可以看出,5种配体中的抑菌圈大小顺序为5-Br-Sal-Gly〉5-Br-Sal-Ala〉5-Br-Sal-Met〉5-Br-Sal-Glu〉5-Br-Sal-Tyr,其中5-Br-Sal-Gly的抑菌圈直径最大。通过比较5-Br-Sal-AA及其与铜(II)形成配合物的抑菌圈直径可以看出,配合物的抑菌活性均高于相应配体的抑菌活性。[结论]氨基酸R基团体积直接影响配体及配合物的抑菌活性,R基团体积越大,抑菌活性越弱。配体与铜(II)形成配合物后其抑菌活性增强。  相似文献   

18.
Atom transfer radical polymerization is a versatile technique for exerting precise control over polymer molecular weights, molecular weight distributions, and complex architectures. Here, we show that an externally applied electrochemical potential can reversibly activate the copper catalyst for this process by a one-electron reduction of an initially added air-stable cupric species (Cu(II)/Ligand). Modulation of polymerization kinetics is thereby tunable in real time by varying the magnitude of applied potential. Application of multistep intermittent potentials successfully triggers initiation of polymerization and subsequently toggles the polymerization between dormant and active states in a living manner. Catalyst concentrations down to 50 parts per million are demonstrated to maintain polymerization control manifested in linear first-order kinetics, a linear increase in polymer molecular weight with monomer conversion, and narrow polymer molecular weight distributions over a range of applied potentials.  相似文献   

19.
本文讨论福建省水稻土分类。把水稻土分为三个亚类型:渗育性水稻土、潴育性水稻土、潜育性水稻土。土属的划分是以起源土壤中的粘土矿物组合和母质的不同而分为八个属:1、砖红壤性土或中更新世海成阶地红土;2、白土或晚更新世海成阶地原生土;3、红壤或晚更新世红土;4、紫色土或紫色砂页岩风化残积物;5、黄壤或山地黄壤;6、冲积土或河流冲积物;7、盐土或滨海沉积物;8、石灰性土及石灰岩残积物。土种的划分是根据土壤上部土层(0~50 cm)的质地构型或耕作层的熟化度。水稻土的命名建议采用地名——亚类(简称)——属名(简称)——上层(0~20cm)质地的连名法,似较现行的命名法切实可用。  相似文献   

20.
From ab initio calculations on various clusters representing the La2-xSrxCu(1)O(4) and Y(1)Ba(2)Cu(3)O(7) classes of high-temperature superconductors, it is shown that (i) all copper sites have a Cu(II)(d(9))oxidation state with one unpaired spin that is coupled antiferromagnetically to the spins of adjacent Cu(II) sites; (ii) oxidation beyond the cupric (Cu(II)) state leads not to Cu(III) but rather to oxidized oxygen atoms, with an oxygen ppi hole bridging two Cu(II) sites; (iii) the oxygen ppihole at these oxidized sites is ferromagnetically coupled to the adjacent Cu(II)d electrons despite the fact that this is opposed by the direct dd exchange; and (iv) the hopping of these oxygen ppi holes (in CuO sheets or chains) from site to site is responsible for the conductivity in these systems (N-electron band structures are reported for the migration of these localized charges).  相似文献   

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