Chemical reaction modeling of industrial scale nitrocellulose production for military applications

A model was developed to describe the nitration of cellulose in mixed acids used in the production of military grade nitrocellulose. Acid dissociation, swelling, diffusion, and chemical reaction were considered to model the nitration of industrially important cellulose materials for given reaction times and conditions. This model is supported by experimental work conducted to measure the dynamics of swelling and diffusion in wood pulp slivers, and the model was validated using the results of lab-scale nitration reactions. Microcomputed tomography was also used to perform a structural analysis of wood pulp slivers that were cut on industrial, rotary cutting machines to evaluate features that may influence the reactivity of these materials.     

复合材料在飞机和汽车上的应用动向(一)

复合材料大量用于航空航天工业和汽车工业,特别是先进碳纤维复合材料用于飞机尤为值得注意。不久前,碳纤维复合材料只能在军用飞机用作主结构,但是,由于技术发展的进步,先进复合材料已开始在民航客机上也应用作主结构,如机身、机翼等。在民航客机上使用复合材料的决定,只有波音公司和空车公司这样的拥有雄厚的人力、财力和胆识的大飞机制造公司才可能作出。至于汽车上,主要使用玻纤增强塑料(热固性和热塑性塑料)用作车身、发动机室内零部件、车顶和进气路管;碳纤维复合材料近年来也日益增多的用于汽车上,主要用作车身外板、车门、进气路管和活门盖等。     

Electrocoagulation pretreatment of seawater prior to ultrafiltration: Bench-scale applications for military water purification systems

The objectives of this research were to investigate the use of in-line electrocoagulation (EC) as a pretreatment for seawater prior to ultrafiltration (UF) at the bench-scale and to compare EC with equivalent doses of ferric chloride. UF membrane performance was evaluated by transmembrane pressure (TMP) and hydraulic resistances at sub- and super-critical fluxes, and by flux recovery after hydraulic and chemical cleanings. Modified Atlantic Ocean seawater was used. Constant flux UF operation (50 to about 350 lmh) was used to evaluate short-term performance at sub- and super-critical fluxes, and constant feed-pressure (15 psi) experiments were used to investigate filter cake stability under high TMP conditions. In-line EC improved UF membrane performance for all coagulation and flux conditions. Compared to no coagulant pretreatment, ferric chloride improved UF membrane performance under short-term, constant flux conditions that resulted in TMP < 8 psi, but produced increased TMP and resistance to filtration at 15 psi. EC always resulted in lower resistance and improved flux recovery after cleaning compared to an equivalent dose of ferric chloride. Overall, EC is a feasible and competitive pretreatment strategy at the bench-scale, but scale-up issues, electrode cleaning requirements, and sustainability during long-term operation need further study.     

Electrocoagulation pretreatment of seawater prior to ultrafiltration: Pilot-scale applications for military water purification systems

The objectives were to investigate the performance of a pilot-scale electrocoagulation (EC) reactor and to determine the feasibility of using in-line EC as a pretreatment to ultrafiltration (UF) of seawater. Work was conducted at Port Hueneme, CA, using components of a U.S. military water purification system. Ferric chloride in-line coagulation was also tested. Both the EC and ferric chloride pretreatments improved UF membrane performance compared to UF without in-line coagulation. EC resulted in slightly greater increases in transmembrane pressure (TMP) than observed following ferric chloride pretreatment during sub-critical flux UF. Substantial accumulation of precipitates developed on the EC electrodes during the testing period. X-ray diffraction identified magnetite, maghemite, lepidocrocite, and akaganeite phases. Accumulation of these precipitates was due in part to conservative hydraulic design of the EC unit. It is recommended that EC units should be designed with short hydraulic retention times and higher electrode current density in order to increase upflow (scour) velocity and thus inhibit accumulation on the electrodes. Progressively longer cycling times for polarity reversal are also recommended. This research indicates that EC offers the potential for a feasible and effective pretreatment strategy for mobile water production facilities.     

抗击疫情,中国日化在行动

1纳爱斯集团一场突如其来的新冠肺炎疫情席卷全国,纳爱斯作为中国洗涤行业领军企业、浙江省疫情防控应急物资重点企业,在这场“大考”中“急政府所急、想百姓所想、保市场所需”,第一时间启动应急预案并成立防控工作指挥部,全面落实企业防疫工作、主动联系中华慈善总会爱心驰援疫区、加紧复工复产保障消毒除菌产品的市场急需供应,以不畏艰难、迎“疫”而上的奋斗姿态,深受社会各界的赞誉。     

人类与传染病的斗争由来已久

[<日本经济新闻>]世界对非典型肺炎的反应似乎有些过激.非典型肺炎的死者已经超过了100人.     

把握质量关 拓宽大市场

黄麦岭磷化工公司通过确定质量目标、建立质量管理网络、提高员工素质及服务质量、争创国家优质工程等措施优化产品结构,磷肥质量六年上了四个台阶,淘汰了四级品、升到一级品,使市场不断扩大。     

Developments in coatings for military vehicles

Conclusions  The MOD operates a wide range of transportation equipment and to ensure that these systems are able to operate in a range of environments a suite of advanced coatings are needed. Environmental legislation has provided a major impetus to introduce new coatings but in addition to the introduction of materials with low solvent contents it has provided an opportunity to introduce materials with improved performance. Unique to the military environment is the need to develop new materials with specific properties to counteract electromagnetic surveillance techniques. In order to undertake this work, knowledge relating to the interaction of electromagnetic radiation with matter as well as paint technology is needed. A third driver in the pursuit of advanced coatings is the need to seek cost effective technology in an age when government departments are under pressure to provide greatest value for money.     

丁腈橡胶/聚氨酯复合材料用相容剂的合成及复合材料的性能研究

利用端羟基液体丁腈橡胶（HTBN）分别与二苯基甲烷二异氰酸酯（MDI）和对氯苯基异氰酸酯（4CPI）反应制备HTBN-聚氨酯（PU）和HTBN-4CPI两系列相容剂,研究其对采用机械共混法制备的丁腈橡胶（NBR）/PU复合材料性能的影响。结果表明：加入相容剂后,NBR和PU的相容性得到有效改善,NBR/PU复合材料的拉伸强度和储能模量增大,磨耗性能提高,当HTBN-4CPI质量分数为0.98%时,NBR/PU复合材料的拉伸强度和储能模量最大,磨耗性能最佳,其中拉伸强度增大35%,磨耗量减小56%。     

Principles of an approach for coloring military camouflage

Optimum technology for dyeing serge with water-soluble sulfur dyes by the continuous pad-steam method was developed. It was shown that the colors for the background obtained in dyeing with Thiosol Olive and Diresul Olive-green satisfy camouflage requirements only in the daytime. Optimum technology for dyeing serge with Active Olive Special by continuous pad-steam and pad-thermofixation methods was developed. The background colors obtained in dyeing with Active Olive Special ensures camouflage both in the visible and in the IR region of the spectrum. __________ Translated from Khimicheskie Volokna, No. 2, pp. 53–56, March–April, 2008.