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1.
本文研究了间歇法从钼酸盐中取钼时,各种因素对提钼率的影响,找出了一较适宜的操作条件,对100ppm的含钼溶液,当外相水溶液PH=2.00,内相NaOH浓度Cio=0.9800mol,Roi=3/1,Rew=1/3,搅拌转速400rpm,膜相配方为:3.6%兰-113.9%TBP,87.4%煤油(W/W),一次处理5min即可使提钼率达97%以上,并且乳液在相同条件下连续使用 3次,提钼率仍在90%以上,提高了经济效益,降低了原料成本,而且该实验可望向连续式发展。  相似文献   

2.
研究了辉钼精矿在Na2 CO3 Na2 MoO4 Na2 SO4 体系的熔盐氧化过程 ,探索了不同工艺参数对钼的转化率和脱硫率的影响 .结果表明 ,在熔盐组成为 1∶1,配料比为 1∶10 ,740℃ ,鼓风速度为 5 .95L/min ,鼓风时间为 10min的条件下 ,钼的转化率和脱硫率均可达 99%以上 .熔炼产物经水浸后 ,钼精矿中的钼和硫分别以Na2 MoO4 和Na2 SO4 形态进入溶液 ,以SO2 形态进入熔炼尾气中的硫不超过总硫量的 0 .8% .  相似文献   

3.
制备一种可回收的磁性复合纳米光催化材料CoFe2O4/g-C3N4, 并对其表面形貌、元素和化学组成、比表面积、官能团特征和晶体结构进行表征与分析。以环丙沙星(CIP)为代表性污染物, 在不同温度(300oC, 400oC和500oC)和复合比例(CoFe2O4:g-C3N4 = 10%, 20%和40%, w/w)条件下, 考察磁性CoFe2O4/g-C3N4复合纳米材料的光催化降解能力。结果表明, 在优化的制备条件下, 投加0.9 g/L CoFe2O4/g-C3N4时, 对10 mg/L CIP (pH=6.6)的120分钟光降解率可以达到75.1% ± 0.1%。在外加磁场作用下, 该纳米材料可实现快速分离回收。经过5次循环回收利用后, 光催化能力仍能达到最初效率的 90%以上, 表现出较好的稳定性。荧光发射光谱图显示, CoFe2O4/g-C3N4复合纳米材料中的电子?空穴复合速率显著降低, 可以提高其对CIP的光催化效果。  相似文献   

4.
通过对康宁木霉纤维素酶(C1酶和Cx酶)、酸性蛋白酶活力的比较,筛选出了康宁木霉产酶的最适培养条件.康宁木霉在m(麸皮)∶m(秸秆)=2∶8,氮源为w=1%的NH4NO3,含水量为65%,起始pH值为6.5的条件下培养72h,C1酶活力最高,为191.3U/g;在m(麸皮)∶m(秸秆)=6∶4,氮源为w=1%的(NH4)2SO4,含水量为65%,起始pH值为7.5的条件下培养48h,Cx酶活力最高,为2006.5U/g;在m(麸皮)∶m(秸秆)=8∶2,氮源为w=1%的(NH4)2CO3,含水量为65%,起始pH值为4.5的条件下培养96h,酸性蛋白酶活力最高,为1859.6U/g.  相似文献   

5.
硫酸氢钠催化合成己酸乙酯的研究   总被引:1,自引:0,他引:1  
利用硫酸氢钠作为催化剂合成了己酸乙酯,通过正交试验得出其最佳合成条件为:投料比n(己酸)∶n(乙醇)=1∶2;w(硫酸氢钠)∶w(反应物)=2:100;带水剂w(甲苯)∶w反应物=1∶4,反应时间2h,酯化率达95.0%以上.该催化剂催化效果好,无污染,易分离回收,可重复使用.  相似文献   

6.
对嗜热金属球菌(Metallosphaera sedula)浸出镍钼硫化矿进行了研究,以探求高效可持续的生物冶金方法. 结果表明:有菌组镍的浸出率均在91%以上,而无菌组为77.64%;以亚铁为能源培养的驯化菌组镍和钼的浸出率分别为96.56%和65.43%,非驯化菌组为94.37%和60.20%;起始pH为2时浸出组镍浸出率达97.55%,钼浸出率为62.97%;粒径小于0.048 mm和小于0.077 mm的浸样镍浸出率分别为97.58%和95.37%,钼浸出率分别为64.46%和59.54%;低矿浆质量浓度比高矿浆质量浓度的浸出率高,5 g·L-1矿浆镍和钼的浸出率分别达98.67%和81.87%;在无菌条件下,浸样添加0.5 g·L-1 Fe3+和对照组镍浸出率分别为91.19%和77.64%,钼浸出率为52.25%和50.19%;透析浸出率比非透析浸出率低;金属球菌浸出组比氧化亚铁硫杆菌浸出组的浸出率高,前者镍和钼浸出率分别为94.01%和64.74%,后者仅为67.77%和38.16%.  相似文献   

7.
从西藏传统食品中分离出一株生产胞外脂肪酶的菌株,通过分子鉴定和形态观察,确定其为黑曲霉AN0512.本文优化了AN0512的产酶条件,并研究了粗酶性质.结果表明,采用植物油1%(v/v)、酵母提取物1%(w/w)、KH2PO40.2%(w/w)、MgSO40.05%(w/w)、KCl0.05%(w/w)等组成的培养基,接种量为1.5%(v/v)时,在28℃、180r/min下培养96h后,发酵液中脂肪酶活性最大达到30IU/mL.在30℃、pH7.0的酶反应条件下粗酶的脂肪酶活性达到最大;在60℃时粗酶仍保留60%以上的脂肪酶活性,显示其较好的耐热性;Ca2+、Fe2+、Co2+、Mg2+、Mn2+能促进粗酶的活性,其中Fe2+的促进作用最大.粗酶液中应含有活性较高的、耐热的低温金属脂肪酶.  相似文献   

8.
本文研究了用氯化三烷基苄基铵(7407)萃取分离铼钼的工艺条件。结果表明,7407是铼钼分离的有效萃取剂,铼钼分离系数为2362。经3次逆流萃取,铼和钼的萃取率分别为:99.60%和3.37%。用40%硫氰酸铵溶液对富有机进行3次逆流反萃取,铼的反萃率为99%。萃取剂可再生循环使用。  相似文献   

9.
石油亚砜是一种低毒、价廉的萃取剂。本文对石油亚砜对钼(Ⅵ)的萃取条件和反萃取条件以及萃取的机理进行了研究。结果表明,在室温下,石油亚砜对pH=1.0-2.0、钼(Ⅵ)浓度为0.01-0.1 M的一级萃取率E(%)达到90%以上;一级反萃率也在90%以上;乳化问题亦获得完满解决。经对萃取机理的初步研究,可以认为石油亚砜萃取铝(Ⅵ)是属于离子缔合型萃取体系,被萃物为:  相似文献   

10.
本文研究了CL-7301萃淋树脂从含钼的H_2SO_4-(NH_4)_2SO_4溶液中提取钼的性能。钼的吸附从中性至7N酸度范围内,其吸附率在pH=3附近有一最大值。钼的饱和吸附容量随溶液中钼的平衡浓度的增加而增加,在大于7g·L~(-1)时可达200mg·g~(-1)以上。在低的平衡浓度下仍有较高的吸附量。其分配系数随平衡钼浓度的增加而降低,大于3g·L~(-1)时基本保持不变。流动实验表明,低浓度和小流速条件下柱床的吸附容量可达到静态吸附容量;而在较高钼浓度和高流速下,其动态吸附容量低于静态吸附容量。用氨水洗涤柱床可直接得到钼酸绥,钼的回收率大于99%,该树脂从低钼浓度溶液中提取钼具有较好的吸附特性。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

15.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

19.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

20.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

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