Lational product in the first half of 1950, national security ![]() The year'sĮvelopments were also importantly influenced by the condence in the future evidenced by consumers and investors,Īe near-absence of speculative commodity price fluctuaions, governmental economic policies, and the programsĮsigned to stabilize the flow of consumer income which haveĮen gradually incorporated into the economic framework.Īside from the course of business as a whole, the reductionį defense spending to a level near which it was scheduled toĮmain for some time was perhaps the outstanding economic Ranches of the economy continued to expand, and noĮneral curtailment in consumer buying set in. Hen downswings occurred in some activities, important Ssociated with the fact that, as in earlier postwar periods The moderation and brevity of the business decline were In the autumn production and sales turned Early last year the falling activity of late 1953 gaveĪy to a period of stability which extended through the Make checks payableįor local telephone listing, consult sectionīUSINESS expansion resumed during the latter part of ![]() Made directly with the Superintendent of Documents. Special subscription arrangements, including changes of address, should be Send remittances to anyĭepartment of Commerce Field Office or to the Superintendent of Documents, United States Government Printing Office, Washington 25, D. Subscription price, including weekly statistical supplement, is $3.25 a This work presents the investigation of permethyl pillararene (MP5) as stationary phase for capillary gas chromatographic (GC) separations.The full text on this page is automatically extracted from the file linked above and may contain errors and inconsistencies. ![]() The MP5 capillary column fabricated by the sol-gel coating method exhibited weak polarity and high column efficiency over 4200 plates/m for n-dodecane, n-octanol and naphthalene. Particularly, the MP5 stationary phase displays unique retention for dibromoalkanes, which was found to be closely related with the linker length, and shows high resolving capability for a wide range of positional and structural isomers, including alkylbenzenes, chlorobenzenes and chloronitrobenzenes, naphthalene derivatives, phenols and anilines. Moreover, the MP5 column showed good thermal stability and repeatability and reproducibility with the relative standard deviation in the range of 0.02-0.04% for intra-day, 0.32-0.46% for inter-day and 1.5-3.4% for between-column, respectively. This work demonstrates an promising future of pillararenes as a new type of stationary phase in chromatographic separations. ![]() In this review, we highlight recent significant advancements for the systematic investigation of achiral, planar chiral and chiral configurations of pillararenes. Compared to the traditional macrocyclic molecule, these interesting frame structures have drawn a lot of attention in analytical chemistry and separation science in recent years, due to their unique superiority advantages such as pillar-shaped frame, electron-rich cavity and easy to functionalize. Although considering the abundant research results on pillararenes, there have been few reviews on the synthesis of planar chiral or chiral pillararenes, as well as summarizing from the perspective of separation science.
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