关于提高水准测量精度的方法探讨

水准测量成果必须在司镜、记录、司尺三者密切合作,熟练掌握各自工作的基本方法,才能完成高效率、高精度的水准成果。

Ethylene Stimulation of Rubberwood （Hevea brasiliensis） Increases the Water Permeability of Lumber

Hevea brasiliensis Muell. Arg. is an important industrial crop for natural rubber production. Latex biosynthesis occurs in the cytoplasm of highly specialized latex cells and latex bleeds out when the bark is tapped. Ethylene stimulation acts by increasing latex flow to the cells of inner bark from the latex cells, increasing yield and may affect the physical properties of rubberwood. The aim of this work was to assess the permeability properties of ethylene treated rubberwood （TRW） relative to untreated rubberwood （URW）, because in wood industrial technology, permeability relates to bondability and wood preservative treatments. The Hevea samples were of PRIM 600 strain, from 20-25 years old rubber trees. The TRW rubber trees had been stimulated by ethylene gas for six years. The rubberwood specimens were collected at a single plot of plantation to minimize variations in soil fertility, environmental exposures and silvicultural treatments at Tumbon Chaibury, Amphor Chaibury, Suratthani Province, Thailand. The moisture contents （MC） of fresh rubberwood were significantly different （P 〈 0.05） at 75% for TRW and 64% for URW. The permeability experiment followed Darcy＇s law, and the hydrostatic pressure was controlled. The average 0.005 Darcy water permeability of TRW was significantly higher than the 0.001 Darcy for URW. Water absorptions during 4 h water immersion of rubberwood blocks differed significantly, and TRW had higher absorption than URW also across 6 d of immersion. Scanning electron microscope （SEM） imaging showed anatomical effects that contribute to the fivefold permeability increase.

Preparation and Characterization of a Novel Polyamide Charged Mosaic Membrane

A novel composite charged mosaic membrane(CCMM) was prepared via interfacial polymerization(IP) of polyamine[poly(epichlorohydrin amine) ]and trimesoyl chloride(TMC) on the polyethersulfone(PES) support. Fourier transform infrared spectroscopy(FT-IR) ,environmental scanning electron microscopy(ESEM) ,atomic force microscopy(AFM) and water contact angle analysis were applied to characterize the resulted CCMM.The FT-IR spectrum indicates that TMC reacts sufficiently with polyamine.ESEM and AFM pictures show that the IP process produces a dense selective layer on the support membrane.The water contact angle of the CCMM is smaller than that of the substrate membrane because of the cross-linked hydrophilic polyamine network.Several factors affecting the IP reaction and the performance of the CCMM,such as monomer concentration,reaction time,pH value of aqueous phase solution and post-treatment,were studied.The pure water flux of the optimized CCMM is 14.73 L·m -2 ·h -1 ·MPa -1 at the operating pressure of 0.4 MPa.The values of separation factorαfor NaCl/PEG1000/water and MgCl2/PEG1000/water are 11.89 and 9.96,respectively.These results demonstrate that CCMM is promising for the separation of low-molecular-weight organics from their salt aqueous solutions.

Alcohol/water-soluble porphyrins as cathode interlayers in high-performance polymer solar cells

Three alcohol/water-soluble porphyrins, Zn-TPyPMeI： zinc（II） meso-tetra（N-methyl-4-pyridyl） porphyrin tetra-iodide, Zn- TPyPAdBr： zinc（II） meso-tetra[1-（1-adamantylmethyl ketone）-4-pyridyl] porphyrin tetra-bromide and MnC1-TPyPAdBr： man- ganese（III） meso-tetra[1-（1-adamantylmethyl ketone）-4-pyridyl] porphyrin tetra-bromide were employed as cathode interlayers to fabricate polymer solar cells （PSCs）. The PCvaBM （[6,6]-phenyl C71 butyric acid methyl ester） and PCDTBT （poly[N-9＂- hepta-decanyl-2,7-carbazole-alt-5,5-（4＇,7＇-di-2-thienyl-2＇,3＇-benzothiadiazole）]）-blend films were used as active layers in polymer solar cells （PSCs）. The PSCs with alcohol/water-soluble porphyrins interlayer showed obviously higher power con- version efficiency （PCE） than those without interlayers. The highest PCE, 6.86%, was achieved for the device with MnCl- TPyPAdBr as an interlayer. Ultraviolet photoemission spectroscopic （UPS）, carrier mobility, atomic force microscopy （AFM） and contact angle （0） characterizations demonstrated that the porphyrin molecules can result in the formation of interfacial dipole layer between active layer and cathode. The interfacial dipole layer can obviously improve the open-circuit voltage （Voc） and charge extraction, and sequentially lead to the increase of PCE.