Based on the research on creation of bas-relief molds for production of bas-reliefs made from boiled pineapple leafs conducted by Rachadasak Pengcum of which purpose was to help generate income for members of Pineapple Leaf Paper Community Enterprise Ban Pasang Wiwat Mueang District Chiang Rai Province it was found that the bas-reliefs need further improvements in terms of appearance and durability as well as the use of other natural raw materials to produce them. The researcher therefore has considered developing the previous research by applying other 3 valueless natural materials which include rice straw water hyacinth and banana stem skin to make bas-reliefs for different beautiful surfaces of the products. Also the quality of bas-reliefs has been comparatively investigated by surveying satisfactions of members of the Community Enterprise and visitors to the project towards the bas-reliefs made from rice straw water hyacinth and banana stem skin. The total period of questionnaire distribution was 3 months. There are 59 respondents administering the questionnaires most of whom (43 persons) are female which accounts for 72.88 per cent. The majority of the respondents (25 persons) obtained junior/senior secondary school diplomas or equivalent accounting for 42.37 per cent. 16 respondents or 27.12 percent are 60 years of age. As for satisfactions towards the bas-reliefs made from rice straw 89 times of “strongly agree” was selected whereas 126 times of “pretty much agree” 75 times of “fairly agree” and 5 times of “disagree” were marked by the respondents. Concerning the bas-reliefs made from water hyacinth 87 times of “strongly agree” was selected while 97 times of “pretty much agree” 110 times of “fairly agree” and 1 time of “disagree” were chosen. When asked about the bas-reliefs made from banana stem skin the respondents selected 77 times of “strongly agree” 99 times of “pretty much agree” 110 times of “fairly agree” and 8 times of “disagree”.

This research presents the engineering properties of asphalt (AC 60/70) modified with different ratios of scrap natural rubber. Then select the best properties of the binder to mix asphaltic concrete. From laboratory testing results with adding 7% scrap natural rubber into mixtures for the best results. The properties of asphaltic concrete can be improved by adding 7% scrap natural rubber. For asphaltic concrete Marshall Stability increased with adding scrap natural rubber into asphalt. Moreover the stiffness modulus of asphaltic concrete can be improved 13.53 compared to AC 60/70.

The purpose of this research is to study the effect of safety measure to construction productivity for ceiling activity by studying a construction of buildings in Bangkok. The safety system composed of (1) stable scaffolding system (2) providing clean and not slip walkways on the scaffold (3) installation of handrails not less than 0.90 meters in height (4) installing stairs (5) providing personal protective equipment for workers (6) are responsible for scaffolding and (7) scaffolding permit document. Cost of the safety system is 23908 baht or approximately 33 baht/m2. Productivity rates for prior and after the used of safety system are 1.57 and 1.41 m2. /person/hr. respectively. The productivity declines for approximately 10.19 % the working time for ceiling could take longer for 10.45 % and labor cost could increase for 10.19 %.

การวิจัยฉบับนี้ได้กล่าวถึงการลดระยะเวลาการทำแม่พิมพ์ยางซิลิโคนโดยเร่งความแข็งด้วยอุณหภูมิต่ำ เนื่องจากแม่พิมพ์ยางซิลิโคนใส สามารถเก็บรายละเอียดของชิ้นงานได้ดีและสามารถมองเห็นชิ้นงานด้านในได้แต่แม่พิมพ์ยางซิลิโคนใสใช้เวลาในการแข็งตัวนาน จึงได้ศึกษาและทำการทดลองนำเอาอุณหภูมิความเย็นเข้ามาช่วยในการเร่งการแข็งตัวของซิลิโคนใสโดกำหนดอุณหภูมิเป็น 3 อุณหภูมิ ประกอบด้วย 10 5 0 องศาเซลเซียล แต่อุณหภูมิแบ่งเป็น 3 ช่วงเวลา ประกอบด้วย 2 3 4 ชั่วโมง จึงทำการการทดลองขั้นต่อไป จากการทดลองโครงการลดระยะเวลาการทำแม่พิมพ์ยางซิลิโคนใสโดยเร่งความแข็งด้วยอุณหภูมิต่ำเพื่อหาอุณหภูมิและช่วงระยะเวลาที่เหมาะสมในการเร่งความแข็งของซิลิโคนใส พบว่าที่อุณหภูมิ 5 องศาเซลเซียล ช่วงระยะเวลา 3 ชั่วโมงมีค่าความแข็งใกล้เคียงกับมาตรฐานและมีความเหมาะสมที่สุด เนื่องจากผลการทดลองพบว่าอุณหภูมิและระยะเวลาที่เหมาะสมที่สุดนั้นสามารถลดระยะเวลาการแข็งตัวของซิลิโคนใสได้ 6 ชั่งโมงและมีประสิทธิภาพใกล้เคียงกับชิ้นงานมาตรฐาน

In this research zeolite NaY is successfully synthesized from rice husk silica as agricultural waste material. Iron catalysts on zeolite NaY from wet impregnation Fe/NaY with Fe loading 0.5-10.0 wt% are characterized and investigated for the oxidation of styrene to benzaldehyde. The characterization with wide angle X-ray scattering (WAXS) suggest that loaded iron dispersed on external surface and inside pore of NaY. Moreover the formation of g-Fe2O3 phase is observed on NaY as indicated by soft X-ray absorption spectroscopy. TGA and FTIR measurements of the Fe/NaY also show the formation of nitrate ion. Over the catalysts the oxidation of styrene is enhanced with benzaldehyde being the major whereas styrene glycol acetophenone phenylacetaldehyde styrene oxide and benzoic acid being the minor products. The 2.5wt%Fe/NaY show the good catalytic selectivity in catalytic oxidation of styrene using H2O2 and reaction time at 6 h and the selectivity of the benzaldehyde reached 75%.