EXISTENCE OF GENERALIZED WEAKLY SOLUTIONS OF DIFFERENTIAL EQUATIONS IN PRODUCT SPACES

In this paper, by using Lyapunov function and weak noncompactness conditions, we give an existence theorem of generalized weakly solutions of Cauchy problem of differential equations in product spaces.     

Determining the wax content of crude oils by using differential scanning calorimetry

By the use of differential scanning calorimetry (DSC), a new method to measure the wax content of crude oil has been developed. In this paper, the wax content of a crude oil is proposed and proved to be the Q (total thermal effect of wax precipitation in sample) ratio of the crude oil and its corresponding wax obtained by using standard acetone method, i.e. Q_oil/Q_wax. For the 14 studied crude oils with the wax content ranging from 1 to 27 wt.%, the wax contents determined by the presented method are in good agreement with those determined by standard acetone method, with an absolute average deviation of only 0.82 wt.%. This method has an advantage over reported DSC methods in which the exact dissolution or precipitation enthalpy of wax is a must. It is also found that the wax contents determined by either of the two methods show good linear relationship with the total thermal effect Q_oil, with the correlation coefficients over 0.96. According to the empirical correlations, the wax content of a crude oil can be easily determined by using the DSC total thermal effect Q_oil. In addition and more significantly, the new method can be applied to improve the accuracy in determining the amount of precipitated wax in a waxy crude oil at different temperatures.     

PPh3/I2/HCOOH: An efficient CO source for the synthesis of phthalimides

A straightforward and general method has been developed for the synthesis of phthalimide derivatives from 2-iodobenzamides and PPh₃/I₂/HCOOH in the presence of a catalytic amount of Pd(OAc)₂. The reaction results demonstrate that PPh₃/I₂/HCOOH is a facile, efficient and safe CO source. The whole process is carried out in toluene at 80?°C and furnishes the desired products in good to excellent yields.     

Comparative in vivo constituents and pharmacokinetic study in rats after oral administration of ultrafine granular powder and traditional decoction slices of Chinese Salvia

Salvia miltiorrhiza, one of the most well‐known herbal medicines, is commonly used for the treatment of coronary heart diseases in China. Besides traditional decoction slices (TDS), another relatively new product of S. miltiorrhiza, ultrafine granular powder (UGP; D90 < 45 μm), is also increasingly being used. In this paper, a UHPLC‐LTQ‐Orbitrap MS technique was developed for a metabolite profile study after oral administration of UGP and TDS of S. miltiorrhiza. The results showed that the number of in vivo absorbed compounds from UGP was much greater than that from TDS, and different types of products from S. miltiorrhiza will have different metabolic processes in vivo. Furthermore, a UHPLC‐Q‐Trap MS/MS method for simultaneously determining four tanshinones (tanshinone IIA, dihydrotanshinone I, tanshinone I and cryptotanshinone) was established and applied to assess the pharmacokinetics of the two types of products. All of the analytes displayed significant higher area under the concentration–time curve and peak concentration after oral administration of UGP than after TDS, indicating that ultrafine powder product could improve the bioavailability and absorption of cryptotanshinon,tanshinone II A,dihydrotanshinonE I and tanshinone I in vivo. The present study provides scientific information for further exploration of the pharmacology of these two types of S. miltiorrhiza and offers a reference for clinical administration of S. miltiorrhiza.     

叶绿素降解产物的环丙基化及其二氢卟吩衍生物的合成

以叶绿素降解产物脱镁叶绿酸-a甲酯为起始原料,利用其二氢卟吩大环上的活性反应区域,沿着N21-N23轴向进行官能团修饰,通过1,3-偶极环加成反应、Grignard反应和外接环的结构改造,在周环上的不同位置上引进了三元环烷基结构,完成了一系列未见报道的叶绿素类二氢卟吩衍生物的合成,其化学结构均经UV,IR,1H NMR,MS及元素分析予以证实,同时也讨论了环丙基的引进对二氢卟吩的理化性质所产生的各种影响,并对部分新化合物的体外光动力活性进行了测试.     

Calcium Sulfite Solids Activated by Iron for Enhancing As(III) Oxidation in Water

Desulfurized gypsum (DG) as a soil modifier imparts it with bulk solid sulfite. The Fe(III)–sulfite process in the liquid phase has shown great potential for the rapid removal of As(III), but the performance and mechanism of this process using DG as a sulfite source in aqueous solution remains unclear. In this work, employing solid CaSO₃ as a source of SO₃²⁻, we have studied the effects of different conditions (e.g., pH, Fe dosage, sulfite dosage) on As(III) oxidation in the Fe(III)–CaSO₃ system. The results show that 72.1% of As(III) was removed from solution by centrifugal treatment for 60 min at near-neutral pH. Quenching experiments have indicated that oxidation efficiencies of As(III) are due at 67.5% to HO^•, 17.5% to SO₅^•− and 15% to SO₄^•−. This finding may have promising implications in developing a new cost-effective technology for the treatment of arsenic-containing water using DG.     

6H－1，2－氧硫杂环己烷并［5，6－c］异苯并吡喃类衍生物的合成及其抗炎活性

６Ｈ－１，２－氧硫杂环己烷并［５，６－ｃ］异苯并吡喃类衍生物的合成及其抗炎活性王进军，崔昌亿，韩光范，魏永慧，姜贵吉（吉林化工学院精细化工系吉林１３２０２２）（吉林医学院检验系吉林）（延边大学化学系延吉）关键词异苯并二氢吡喃，杂环化合物，抗炎活性可用...