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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
451

A Study on Seed Morphology of Melastomataceae in Taiwan

Huang, Yu-Feng 23 July 2007 (has links)
The seed external morphology and seed coat pattern of 11 genera and 22 species of Melastomataceae in Taiwan were studied by dissecting microscopey and scanning electron microscopey. According to the seed size, the result showed that the length and width of seed is different inter-generically. The biggest size is the seed of Memecylon while contrast to those of the other genera. The seed shapes could be divided into 8 types. They are liner-lanceolate, cuneate, fusiform, reniform, cochleate, triangular, obovoid and parallelogram respectively. Except that of the Sarcopyramis, the seed shape is rather stable intra-generically. The seed coat could be classified into 6 patterns. They are verrucate, rugose, smooth, tuberculate, granulate, and colliculate respectively. The seed colors are egg-yellow, brown, nut-brown and reddish brown. The difference of seed morphology is obvious inter-generically, and the difference of seed coat patterns is extinctive intra-generically.
452

Revision of the mole genus Mogera (Mammalia: Lipotyphla: Talpidae) from Taiwan

Kawada, Shin-ichiro, Shinohara, Akio, Kobayashi, Shuji, Harada, Masashi, Oda, Sen-ichi, Lin, Liang-Kong 05 1900 (has links)
No description available.
453

Morphology and Phase Behavior in Poly(n-alkyl methacrylate) and Poly(n-alkyl acrylate)

Wu, Yun-Sheng 16 July 2000 (has links)
In this research,we observed PAMA(poly(n-alkyl methacrylate)) and PAA(poly(n-alkyl acrylate)¡^side chain crystalline.We find side chain is longer and crystalize more easily,melting point is higher.In the result of DSC thermograms,the length of side chain is 6 carbons,we can't find any thermal transition.But the length of side chain is 12¡B18 carbons,we only found Tm.In PLM observation,we only get side chain crystalline's picture,and can't see any liquid crystalline yet. Although in X-ray's illustrative can find layer structure's diffraction peak,but i think this evidence can't prove the system that is liquid crystalline.It just can be said that the layed structure was formed by side chain crystallization.
454

µL

Su, Min-Chen 26 July 2000 (has links)
none
455

Morphology and possible function of Sepiella japonica Sasaki, 1929 (Sepiidae: Cephalopoda: Mollusca).

Hsueh, Meng-Min 29 July 2002 (has links)
The gland in the posterior end of Sepiella is a conspicuous structure, and is a diagnostic character of the genus Sepiella. Researches on this gland were few, with only Steenstrup¡]1879-80¡^described its morphology, and he thought it was very peculiar. One species of the genus Sepiella, S. japonica is a common species in fish markets in Taiwan; therefore, it was used to study the gland. Sasaki (1929) named the gland as the caudal gland, and it is followed here. The caudal gland is located at the posterior end of the mantle, along the midline, in between the two fins, and between the dorsal skin and the cuttlebone. The caudal gland is an egg-shaped cavity, and the walls of the cavity have many vertical folds. There is brown liquid in the cavity, and the liquid contains dark brown granules. The outer opening of the cavity is in the cleft between two fins, in the junction of fins and mantle, but closer to the ventral skin. There are iridophores in the connective tissue of the hypodermis of the dorsal skin above the caudal gland. As the cephalopod can control the activities of chromatophores, S. japonica may have the ability to control the expression of the caudal gland. There are circular muscles, posterior fin conjunctive muscle, surrounding the caudal gland, so we consider that the caudal gland can emit the secretions at well, and the muscle of the walls of caudal gland can assist to emit the secretions. Development of the caudal gland begins from the ventral side of the caudal gland. In embryo, the caudal gland is a lamellar epidermis. With growth, the front of the caudal gland evaginates and the caudal gland becomes sacciform gradually. The folds of the ventral walls of the caudal gland are more massive and complicated than those of the dorsal walls. There are many pores on the surface of caudal gland¡¦s walls. The secretion can be extruded from those pores. Histological sections of caudal glands indicated that the epidermis of the caudal gland is composed of simple columnar epithelial cells, and that the secretion is secreted from epithelial cells. There are many dark brown granules in the secretion of caudal glands. Some are spherical with a ciliary edge. Some are crystalloid. Some are transparent spherical balloons, and some are basophilic grains. The secretion also contains cells, including circular cells, cells with V- shaped nucleus, and cells with pseudopods. The secretion of caudal glands is organic, and also contains P, S, and Cl etc. The cobia juveniles fed with caudal glands or cuttlefish flesh drenched with caudal gland secretion disgorged the food immediately, indicating the cobias dislike something in the secretion. The length of the caudal gland is about 15.7¢Mof the dorsal mantel length of S. japonica. A positive trend between the caudal gland size and the dorsal mantle length was observed. The caudal gland sizes were not significantly different between male and female. The proportion of caudal gland length to dorsal mantle length of S. japonica was not significantly different between mature and immature individuals. The proportion was also not significantly different among seasons. It is concluded that defence is among the functions of the caudal gland.
456

Heat of Fusion, Crystallization Kinetics Analyses and Morphology of Poly[(ethylene)-co-(trimethylene terephthalate)]s

Wang, Chuan-Liang 01 July 2003 (has links)
These developmental grade samples were supplied by the Union Chemical Laboratories of Industrial Technology Research Institute(ITRI). The compositions of a series of copolyesters were identified by C1-NMR and H1-NMR. The ethylene terephthalate(ET) units are 8.9¡B33.7¡B37.9% and trimethylene terephthalate(PT) units are 91.1¡B66.3¡B62.1% in the copolyesters with sample codes of C2¡BC3¡BC4. Differential scanning calorimeter(DSC) was used to study the isothermal crystallization kinetics and melting behaviors and Polarizing Microscope(PLM) was used to study the spherulite growth rates and spherulite patterns. The Hoffman-Weeks linear plot and M-X nonlinear plot gave an equilibrium meiting temperature(Tmo ) oC of C2¡BC3¡BC4 are (240.6¡B275.5)¡B(208.8¡B247.0)¡B(194.3¡B229.4). The growth rates (£gm/s )of different samples in the different crystallination temperature(Tc) oC are C2(0.614~0.061, 180~207)¡BC3(0.112~0.021, 130~166)¡BC4(0.0213~0.003, 120~160). From the different equilibrium meiting temperature(Tmo ) and different T¡Û = ( Tg-30, Tg-51.6 oC) to analysis the regime transition temperature (T¢º¡÷¢») in units of oC are C2(234.0¡B237.1¡B240.6¡B275.5¡A195.9¡Ó0.3, 196.2¡Ó0.4)¡BC3(193.1¡B198.9¡B208.8¡B247.0¡A147.5¡Ó0.2, 147.5¡Ó0.1)¡BC4(184.1¡B187.9¡B194.3¡B229.4¡A133.3¡Ó0.4, 133.6¡Ó0.2). Compare the results with the results that using the half-time of crystallization(t1/2) from DSC (C2(193.6 oC)¡BC3(147.3 oC)¡BC4(1140.4 oC)). It can find that C2 is over 2.3 and 2.6 oC and C3 is the same and C4 is under 6.8 and 7.1 oC. From the morphology of spherulite patterns and regime transition temperature (T¢º¡÷¢») oC, the results indicated that the change from the morphology is closed to regime transition temperature. Regular spherlites were exhibited at temperature(Tc) between 180 and 196 oC and banded spherulites were observed between 197 and 208 oC in the C2. The band spacing increase with increasing crystallization temperature. Regular spherlites were exhibited at temperature(Tc) between 130 and 147 oC and banded spherulites were observed between 148 and 172 oC in the C3. The band spacing increase with increasing crystallization temperature. Regular spherlites were exhibited at temperature(Tc) between 120 and 134 oC and banded spherulites were observed between 135 and 160 oC in the C4. The band spacing increase with increasing crystallization temperature. Combine the results of M-X plot and spherulites pattern and melting behaviors at a heating rate of 80 oC/min . It indicated that the regime transition temperature (T¢¹¡÷¢º) oC are in the range of crystallization temperature of C2¡BC3¡BC4 are (210~213¡B174~178¡B160~164 oC). The heat of fusion (¡µHu) of C3 is 4.88¡Ó0.06 kcal/mol and B is 1.47¡Ó0.05 cal/c.c from the experimental. The heat of fusion(¡µHu) of C4 is 2.56¡Ó0.22 kcal/mol and B is 4.45¡Ó0.36 cal/c.c from the experimental. Compare the results with PET(¡µHu = 5.6 kcal/mol) and PTT(¡µHu = 7.2 kcal/mol). It indicated that PTT > PET > C3 > C4.
457

Synopsis of the morphology and taxonomy of Carex section Glaucescentes in North America

McLaughlin, Diane Coston 15 November 2004 (has links)
Field studies were used to characterize habitat and evaluate morphological characters of Carex glaucescens, C. joorii and C. verrucosa. Morphometric analysis of herbarium specimens along with field studies, Environmental Scanning Electron Microscopy (ESEM), pollen viability and phenology show C. glaucescens, C. joorii and C. verrucosa to be taxonomically distinguishable at the species level. The taxonomy of Carex section Glaucescentes is presented in an artificial dichotomous key to the taxa and in species descriptions.
458

Crack healing as a function of pOH- and fracture morphology

Fallon, Jessica Anne 17 February 2005 (has links)
Crack healing in quartz has been investigated by optical microscopy and interferometry of rhombohedral ( 1 1 10 ) cracks in polished Brazilian quartz prisms that were annealed hydrothermally at temperatures of 250°C and 400°C for 2.4 to 240 hours, fluid pressure Pf = Pc = 41 MPa, and varying pOH- (from 5.4 to 1.2 at 250°C for fluids consisting of distilled water and NaOH solutions with molalities up to 1). Crack morphologies before and after annealing were recorded for each sample in plane light digital images. Crack apertures were determined from interference fringes recorded using transmitted monochromatic light (l = 598 nm). As documented in previous studies, crack healing is driven by reductions in surface energy and healing rates are governed by diffusional transport; sharply defined crack tips become blunted and split into fluid- filled tubes and inclusions. A rich variety of fluid inclusion geometries are also observed with nonequilibrium shapes that depend on initial surface roughness. Crack healing is significant at T=400°C. Crack healing is also observed at T=250°C for smooth cracks with apertures <0.6 mm or cracks subject to low pOH-. The extent of crack healing is sensitive to crack aperture and to hackles formed by fine-scale crack branching during earlier crack growth. Crack apertures appear to be controlled by hackles and debris, which prop the crack surfaces open. Upon annealing, crack apertures are reduced, and these reduced crack apertures govern the kinetics of diffusional crack healing that follows. Hackles are sites of either enhanced or reduced loss of fluid-solid interface, depending on slight mismatches and sense of twist on opposing crack surfaces. Hackles are replaced either by healed curvilinear quartz bridges and river patterns surrounded by open fluid-filled crack, or by fluid- filled tubes surrounded by regions of healed quartz. For a given temperature, aperture and anneal time, crack healing is enhanced at low pOH- ( £ 1.2) either because of changes in the hydroxylated quartz- fluid interface that enhance reaction rates or because of increased rates of diffusional net transport of silica at high silica concentrations.
459

Comparative feeding biomechanics and behavioral performance of feeding in the family kogiidae and tursiops truncatus (odontoceti, cetacea)

Bloodworth, Brian Edward 17 September 2007 (has links)
Hyolingual biomechanics and kinematics in three species of two odontocete genera were investigated to compare adaptations and performance of divergent feeding strategies. Ram and suction feeding are two ends of a continuous spectrum that is poorly-studied in odontocetes. Comparative anatomy identified characters associated with feeding patterns of morphologically dissimilar and evolutionary distant genera. Hyolingual investigations included measurements of hyolingual muscle vectors and hyoid surface area/robustness. ANOVA's revealed Kogia basihyal and thyrohyal surface areas were significantly greater than T. truncatus. However, most predicted muscle tension values were not significantly different between genera. The presence of lateral gape occlusions, broad basihyal and thyrohyals near the caudal oral cavity, and a broad, short tongue were likely responsible for Kogia's effective suction mechanism. These features were absent, or reduced, in T. truncatus. The feeding kinematics of dwarf and pygmy sperm whales (Kogia sima and K. breviceps), and bottlenose dolphins (Tursiops truncatus) were characterized and compared incorporating the Ram-Suction Index (RSI). Mean RSI data support a suction feeding strategy for the phylogenetically basal Kogia (-0.67; S.D.±0.29) and a ram feeding strategy for the more-derived Tursiops (0.94; S.D.±0.11). Tursiops displayed two ram-based feeding behaviors, closed gape approach, where gape increased near food items, and open gape approach, where gape was at least 50% of maximum in the first video field. Four feeding phases were identified in both odontocetes: preparatory, jaw opening, gular depression, and jaw closing. The mean Kogia feeding cycle duration (470 ms; S.D.±139) was significantly shorter (P<0.003) than all Tursiops groups (pooled: 863 ms; S.D.±337, closed gape approach: 662 ms; S.D.±207, open gape approach: 1211 ms; S.D.±207). Kogia mean maximum gape angle (39.8°; S.D.±18.9), mean maximum opening, and closing gape angle velocities (293°/s; S.D.±261 and 223°/s; S.D.±121, respectively) were significantly greater (P<0.005) than pooled Tursiops mean maximum gape angle (24.8°; S.D.±6.6), mean maximum opening and closing gape angle velocities (84°/s; S.D.±56 and 120°/s; S.D.±54, respectively). Negative Kogia RSI values were correlated with increasing maximum hyoid depression and retraction, wide gape angle, and rapid opening gape velocity. Kinematic data support functional hypotheses that odontocetes generate suction by rapid depression of the hyoid and tongue.
460

Field survey and culture studies of Caulerpa in Taiwan

Shi, Chien-Hung 31 January 2008 (has links)
¡§ Sea grape ¡¨ named by Japanese is Caulerpa lentillifera having erect branches with spherical ramelli. The length observed in field is 3 cm but may elongate over 10 cm after cultivation. While it is generally recognized by Taiwanese for all edible Caulerpa with spherical ramelli. Caulerpa microphysa collected from Taiwan northeast coast having 3 cm erect branch, but was recorded as 1 cm. To find the Caulerpa with longer erect branch field survey was conducted monthly in Taiwan south coast¡]Hsiao Liu Chiu and Kenting¡^ for one year from October 2006. Six species including C. racemosa var. macrophysa, C. microphysa, C. peltata, C. serrulata, C. sertularioides and C. racemosa var. turbinata were collected. The other two species C. lentillifera and C. racemosa var. occidentalis are acquired from the aquaculture ponds. In total 8 Caulerpa species are cultivated in aquariums with steady flow and nutrients. After cultivation, the morphology of C. racemosa var.macrophysa and C. peltata changed largely. All species with spherical ramelli only had 3-4 cm erect branches, but the C. microphysa strain from the northeast coast could elongat to 12 cm, having the same growth character as the Japanese sea grape. The morphology of the erect branches of C. microphysa changed with the temperature and the illuminance. Caulerpa microphysa could grow in 25-40 psu salinity, at 22-31.5 ¢J and 100-400 £gE/m2/s, the best growth rate¡]26.4 ¡Ó 0.6 ¢H/day¡^found in 35 psu salinity, at 31.5 ¢J and 100 £gE/m2/s. The growth of C. microphysa in deep seawater was better than in the surface seawater, that indicated there are some special nutrients in the deep seawater for the Caulerpa and need to study in the future.

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