与化学有关的英语论文

impossible between members of different species because genitals of males and females are structurally incompatible or because molecules on the surfaces of sperm and egg fail to A final type of prezygotic mechanism is temporal isolation, in which time-related environmental cues that trigger reproductive processes are different for related 有时，产生前合子隔离的差异涉及了隔离机制。即，由于生殖器结构不匹配或精卵分子表面不结合而使不同种群成员间不能自然结合。最后一类前合子机制是暂时隔离，与时间有关的环境因素触发了相关物种的不同繁殖过程。

1In the first study to look at what happens over the years to the billions of pounds of plastic waste floating in the world's oceans, scientists are reporting that plastics — reputed to be virtually indestructible — decompose with surprising speed and release potentially toxic substances into the 2Chemicals are an important aspect in our economy and serves with many However, when chemicals are not properly used they can create a problem with global There is the threat of chemical spills and also a possible use by Many chemicals are stored and processed at numerous If terrorists were to attack any chemical plants in the United States it would kill more than 2 million There is also a long-term threat of contamination that will affect both people and the These chemicals can contaminate the water and cause many illnesses to In 1962, Rachel Carson informed the public about the horrible effects that DDT had on the environment and health problems of But it took 10 years for the United States to ban this But not all chemicals pose a security To reduce the use of chemicals facilities are required to provide the public with annual chemical This has allowed our society to force these facilities to use these chemicals better and The Stockholm Convention on Persistent Organic Pollutants came into effect in May This treaty would ban or restrict the production and use of 12 hazardous There will always be an abundance of chemicals but their use needs to be lowered to make them less of a 3A captain of a ship drunkenly crashes a massive oil tanker along a reef and changes the physical and emotional world Chemical spills are major problems that plague the Strict government regulation is trying to aid with this problem, but governmental leaders face many Disposal of harmful chemicals is often difficult and Since chemical waste has destroyed the environment, steps are being taken to prevent further 看看，参考一下吧：

有机化学英语论文Abstract In this work the effects of the microporosity and chemical surfaceof polymeric adsorbents on adsorptive properties of phenol Textural parameters of four kinds of polymeric resins namely AB-8 D4006 NKA-II and D16 resin were separately measuredby ASAP The surface chemistry of these polymeric resins was determined by means of inverse gaschromatography (IGC) and diffusereflectance infrared Fourier transform spectroscopy (DRIFTS) Static equilibrium adsorption experiments were carried out to obtain theisotherms of phenol on the polymeric It was shown that NKA-II and AB-8 resin possessed relatively high BET surface areas andmicropore volumes while D4006 and D16 resin possessed comparatively low BET surface areas and micropore The results of IGCexperiments revealed that NKA-II resin had extraordinary high specific component of the free energy of adsorption both for polar acetone andbenzene probe and thus extraordinary strong surface polarity compared to the other polymeric It was also found that the isotherm ofphenol on NKA-II was much higher than that on the other polymeric resins due to its strongest surface polarity and largest micropore volumeamong four kinds of These experimental observations indicated that adsorption of phenol on the polymeric resins depended greatly ontheir microporosity and surface The well-developed microporosity and the strong surface polarity would improve the adsorptionof phenol on the polymeric 2004 Elsevier BV All rights Keywords: Polymeric resin; Phenol; Porosity; Surface chemistry; Inverse gas chromatography