Water is source of life on earth. The largest water body is in the ocean at 97 percent and 3 percent remaining is fresh water which is used to support daily needs, so clean water is a basic human need. The limited amount of water and increasing people number caused a clean water crisis. Apart from the amount, the quality of fresh water is getting worse. The struggle to use clean water for various uses and clean water wasteful behavior had resulted in the loss of adequate access of clean water for some people. One of the ways to improve clean water quality and quantity is conducting a water purification process. Water purification can be done using simple tools with filtration techniques. Through the Community Partnership Program’s theme "Education of Simple Water Purification as an Effort to Fulfill Clean Water Needs" able to provide knowledge and understanding to teachers and students of MTs Nurul Qur'an Jakarta as activity partners.

Concrete currently consists of several types. Among them are Fibrous Concrete, Lightweight Concrete, SCC Concrete, Hollow Concrete etc. All have advantages and disadvantages to each. The use of various types of concrete is adjusted to the needs of construction. In this research, fibrous steel concrete with a combination of silica fume will be the main object to be studied. So far, fibrous concrete has been actively studied in various countries. From the results of previous studies, fibrous concrete can improve the quality of concrete, especially reducing the brittle nature and initial cracking in concrete. While Silica Fume can increase the compressive strength of concrete. The main objective of this study to determine and understand the mechanical properties of concrete with a combination of steel fibre and silica fume such as compressive strength and split tensile strength. The percentage of steel fibre percentage used in this study is from 0 to 3 per cent, while the percentage of silica fume used is l0 per cent by weight of cement. The results of a study are the optimum compressive strength is in the DFl variation with the percentage of silica fume l0 per cent and 0 per cent steel fibre. The use of steel fibre combined with silica fume does not significantly affect the compressive strength. Although it tends to decrease the compressive strength. The strength of tensile strength obtained ranges from 11 to 14 per cent of the compressive strength.

Papan partikel tanpa perekat sintesis atau binderlessboard merupakan alternatif produk ramah lingkungan yang potensial dikembangkan di Indonesia. Kelemahan produk tersebut diantaranya adalah kestabilan dimensinya yang relatif rendah. Alternatif perbaikan produk bisa dilakukan dengan menambahkan bahan pengaktif komponen kimia. Asam sitrat memiliki tiga gugus karboksil dan diharapkan dapat membentuk ikatan ester dengan gugus hidroksil pada permukaan kayu. Penelitian menggunakan asam sitrat relatif baru dan belum banyak dikembangkan, oleh karena itu penelitian ini ditujukan untuk pengembangan produk biokomposit dengan menggunakan asam sitrat sebagai bahan pengikat. Bahan yang digunakan adalah pelepah nipah dengan ukuran partikel (halus dan kasar), konsentrasi asam sitrat (0% dan 10%), dan suhu pengempaan (180ºC dan 200°C). Pengujian sifat fisika dan mekanika dilakukan berdasarkan Japanese Industrial Standard untuk papan partikel (JIS A 5908). Penambahan asam sitrat memperlihatkan kenaikan sifat fisika (penyerapan air) dan mekanika papan partikel. Perbedaan ukuran partikel mempengaruhi sifat mekanika papan partikel dimana ukuran partikel kasar memberikan nilai mekanika yang lebih baik dibandingkan dengan ukuran partikel halus. Kualitas papan partikel optimum diperoleh pada kondisi pengempaan 180ºC, penambahan asam sitrat 10% dari partikel ukuran kasar dengan nilai pengembangan tebal 2,4%, penyerapan air 41%, kekuatan rekat internal 0,2 MPa, modulus patah 5,5 MPa, dan modulus elastisitas 1,6 GPa.Kata kunci: asam sitrat, pelepah nipah, konsentrasi asam sitrat, suhu pengempa Effect of Citric Acid Concentration and Pressing Temperature on the Quality of Particleboard from Nypa FrondAbstractBinderlessboard is one of the potential eco friendly products that can be developed in Indonesia. However, its boards usually have low in dimensional stability. Addition of the chemical agent, such as citric acid, that can improve the dimensional stability is needed. Citric acid has three hydroxyl groups that can be ester-linked with hydroxyl groups from wood. Researches on citric acid and its utilization are relatively limited. This research focused on the development of particleboard using citric acid as bonding agent. Nypa frond was used as raw material with two different sizes of particles, namely fine and coarse particles. Addition of citric acid of 10% air-dried particles was done for improving the dimensional stability. Pressing temperature was set at 180ºC dan 200°C during 15 minutes. Physical and mechanical properties were done according to Japanese Industrial Standard JIS A 5908. Addition of citric acid could improve physical and mechanical properties of the boards. Coarse particles provided the particleboards with better mechanical properties compared to fine particle. Boards that made from coarse particle and 10% citric acid at pressing temperature of 180ºC have optimum properties, i.e. thickness swelling 2.4%, water absorption 41%, internal bond strength 0.2 MPa, modulus of rupture 5.5 MPa, dan modulus of elastisity 1.6 GPa.

Concrete is a very popular construction  material, widely  used in construction. The waste that is in the surrounding environment begins to be used for mixed materials in the manufacture of concrete, one of which is geothermal mud (geothermal sludge) which has pozzolanic properties because it contains alumina silica minerals so that it can be used instead  of cement. Waste steel fiber tires used residue from vehicles is an added material that can be used to improve the mechanical properties of concrete. This study aims to determine the effect of adding geothermal mud and used steel fiber to concrete. Planned concrete fc '30 MPa with geothermal mud as partial substitution of 20% cement and used tire steel fibers with variations of  0%, 0.5%, 1% and 1.5% of the weight of concrete. Concrete Variation 4 (1.5% used tire steel fiber + 20% geothermal mud) has the highest compressive strength of 32.13 MPa compared to normal concrete of 30.006 MPa. For the splitting  tensile strength variation 4 is 1.8 MPa and its flexural strength is 2.457 MPa while the normal concrete is splitting tensile strength of 1.6 MPa and its bending strength is 2.210 MPa.

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