次超微量法 的英文怎麼說
中文拼音 [cìchāowéiliángfǎ]
次超微量法
英文
picogram method-
First, this paper gives an introduction of some methods of unequal probability sampling, their estimators and variance estimators, including sampling with pps with replacement, methods of sampling without replacement suggested by brewer, durbin, sampford, des raj, murthy, rao - hartley - cochran. then, at the basis of rao and bayless ' s study, we consider that population can be splited two random subpopulations, which are respectively drawn from different infinite super - populations, and compare the stabilities of estimators of the methods that given above. we find that the minor difference between two super - populations has great effect on the efficiency of the estimators for the population with moderately large coefficient of variation ( c. v. )
本文首先從理論上介紹了若干種不等概率抽樣方法，它們的估計量、估計量的方差及其估計，其中包括有放回ppz及pps抽樣，不放回不等概率抽樣中的brewer 、 durbin 、 sampford 、 desraj ， murthy 、 rao - hartley - cochran等人的方法；其次，在rao和bayless兩人就樣本單元數n = 2的情形對上述抽樣方法進行比較的基礎上，將總體隨機地分成兩個子總體，視每個子總體取自不同的線性超總體，在文中，我們利用計算機實現隨機分組，並通過畫圖比較各方法估計量的穩定性，結果表明，對變異系數c . v . （ x ）較大的總體而言，兩個超總體之間的微小差異將對估計量的穩定性產生很大的影響，從而說明rao和bayless的比較結果還不夠完善。By sims method, we analyzed the profile distribution of mn and c, found that increasing the annealing temperature is beneficial to the diffusion of mn, but has no influence to c. mfm and squid measurements demonstrate that sub micron single - domain magnetic mnas particles found in sample annealing at 850 for 15s show ferromagnetism at room temperature and have a high curie temperature more than 300k
利用二次離子質譜方法對mn和c在樣品中的分佈進行了研究，發現退火溫度的上升，有利於mn的擴散；而對c的分佈影響較小。利用磁力顯微鏡和超導量子干涉儀對樣品的磁性質進行了研究。發現在850 + 15s退火處理的樣品中形成了亞微米級單疇磁性mnas粒子；經測試其在室溫下呈現出鐵磁性，居里溫度在300k以上。The optimum conditions of preparation were as fellows : the concentration of zinc sulfate solution of 1. 8 - 2. omol / l, the concentration of ammonium bicarbonate solution of 1. 4 ~ 1. 6mol / l, the time of ultrasonic radiation of 25 ~ 30min. iv. preparation of active zinc oxide by means of microwave radiation to calcine precursor of basic zinc carbonate firstly, and a mechanism on preparation of ultra - fine active zinc oxide by means of microwave radiation has been investigated emphatically as well as the effects on quality of ultra - fine active zinc oxide have been analyzed and discussed in detail, the time of microwave radiation was 7 ~ 16 min ; comparing microwave radiation calcining with conventional calcining, the calcining time of microwave radiation was one thirty to one twenty, the calcining time shortened hugely, energy consumption saved hugely, the quality of product improved
首次引入超聲波輻射制備超細活性氧化鋅前驅體堿式碳酸鋅新技術，研究了超聲波輻射制備前驅體堿式碳酸鋅的機理，並分析和討論了影響前驅體質量的各種因素，確定了最佳的前驅體制備條件為：硫酸鋅濃度為1 . 8 2 . 0mol / l ，碳酸氫銨的濃度為1 . 4 1 . 6mol / l ，超聲波輻射25 30min ； 4 、首次採用微波加熱煅燒前驅體堿式碳酸鋅制備超細活性氧化鋅的新技術，研究了微波輻射加熱煅燒前驅體制備超細活性氧化鋅的機理，並分析和討論了影響活性氧化鋅質量的各種因素，確定了最佳的超細活性氧化鋅制備條件為：微波加熱煅燒時間為7 16min ，與傳統煅燒方法相比，煅燒時間僅為傳統的1 30 1 20 ，大大縮短煅燒時間，節省能耗，提高了煅燒產品的質量； 5 、完成了從鋅浮渣中制備超細活性氧化鋅的小試試驗和擴大試驗。
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