Ibnu Umar, tokoh sahabat yang terkenal sangat wara’, pernah ditanya,”apakah para sahabat Rasulullah dahulu tertawa?” pertanyaan sederhana, tapi menyiratkan kebutuhan informasi yang akurat tentang karakter sebuah generasi terbaik. Ibnu Umarpun menjawabnya dengan menjawab seobjektif mungkin. “Ya, mereka tertawa, tapi iman di dada mereka laksana gunung.” Begitu jawab Ibnu Umar.

Perhatikan, apa yang melatarbelakangi pertanyaan kepada Ibnu Umar Tersebut. Para sahabat adalah kumpulan manusia pemilik keberanian dan pengorbanan yang tidak ada bandungnnya. Orang yang bertanya kepada Ibnu Umar, tertarik untuk menanyakan sisi kemanusiaan generasi terbaik itu. Dan ternyata, begitulah jawaban Ibnu Umar. Singkat, padat, dan dalam maknanya.


Para sahabat ternkenal sangat giat dalam beramal. Umar ra, bahkan mengatakan, “Aku sangat benci melihat seorang kalian yang menganggur, tidak melakukan amal dunia dan tidak melakukan amal akhirat.” Hari demi hari yang mereka lalui selalu bermakna penngkatan dan pengembangan dari sebelumnya. Ibrahim Al Harbi pernah menceritan perihal imam dari generasi Tabi’in, Ahmad bin Hambal. “Aku telah hidup bersama Ahmad bin Hambal 20 tahun. Selama musim kemarau dan hujan, musim panas dan dingin, siang dan malam. Aku tak pernah mendapatinya, kecuali ia lebih baik dari hari kemarin.” (Manaqib Imam Ahmad bin Hambal, Ibnu Jauzi, h. 140)

Meski demikian, para shalihin itu tetap berada di tengah-tengah, antara kekerasan dan kelembutan, antara disiplin bekerja dan istirahat. Seperti juga Rasulullah menyifatkan dirinya dengan istilah “adhahuuku al-qattal”, orang gemar tertawa tapi gemar juga berperang.

Senyum sebagai bagian dari peristirahatan dan kelembutan, dalam pandangan mereka, bahkan menjadi salah satu sifat istimewa manusia yang tidak dimiliki binatang. Ibnu Taimiyah ra mengulas hal ini dengan uraian y6ang menarik: ”Manusia itu hewan yang bicara dan bisa tertawa. Tak ada yang membdeakan manusia dari hewan, kecuali sifat-sifat kesempurnaan. Sebagaimana bicara menjadi salah satu sifat kesempurnaan manusia, demikian juga dengan tertawa. Maka yang bicara itu lebih sempurna dari yang tidak bicara, begitu pula yang tertawa itu lebih sempurna dari yang tidak mampu tertawa.” (Fatawa Ibnu Taimiyah, 6/121)

Yang perlu diingat, peristirahatan itu baru bisa bermanfaat dengan dua syarat. Pertama, dilakukan dalam waktu sementara dan temporal. Kedua, tidak keluar dari batas-batas yang dibenarkan oleh syariat. Melanggar dua syarat ini berarti substansi peristirahatan akan hilang atau justru memunculakn akibat sebaliknya. Karenanya, tanpa kehati-hatian, peristirahatan dan sebuah jeda, bisa berubah menjadi kelemahan, kemalasan, bahkan keterjerumusan pada tipu daya syaitan.

Peristirahatan, harus tetap patuh pada aturan syariat. Canda misalnya, tak boleh dicampur dengan dusta. Peristirahatan, hanya variasi hidup yang penting dari rutinitas. Ia juga ibarat garam dalam makanan. Penting tapi tak boleh berlebihan. Tokoh ulama Kuwait Syaikh Jasim Muhalhil mengistilahkan hal ini dengan “waktu turun minumnya seorang pejuang”, yang akan mengembalikan stamina atau menghidupkan tenaga yang lebih besar dari sebelumnya. Tokoh ulama Mesir Hasan Al Bana menyebut dengan ungkapan: “Mujahid sejati, adalah tak tidur sepenuh kelopak matanya, dan tidak tertawa selebar mulutnya.” Itulah makna peristirahatan dan perhentian yang hakiki.
Selengkapnya...

by Richard G. Rice
Product Description:
Bridges the gap between classical analysis and modern applications. Following the chapter on the model building stage, it introduces traditional techniques for solving ordinary differential equations, adding new material on approximate solution methods such as perturbation techniques and elementary numerical solutions. Also includes analytical methods to deal with important classes of finite-difference equations. The last half discusses numerical solution techniques and partial differential equations.

* Publisher: Wiley
* Number Of Pages: 706
* Publication Date: 1994-11
* ISBN-10 / ASIN: 0471303771
* ISBN-13 / EAN: 9780471303770
* Binding: Hardcover

Download:
Rapidshare (password: gigapedia.org)
4shared
mihd.net

Selengkapnya...

by H. Scott Fogler
Product Description:
Great structure to ensure principles are clearly understood and can be appliedafter the completion of the book. This is achieved first through a discussion ofcritical thinking and how Socratic questioning is at the heart of criticalthinking, followed by examples of critical thinking questions, and then finallyexercises on critical thinking. Contains more coverage of industrial chemistrywith real reactors and real reactions and extends the wide range of applicationsto which chemical reaction engineering principles can be applied. Through theuse of an interactive CDROM that is shrunk wrapped with the text andcorresponding web page the book and resource material is designed to addressdifferent student learning
styles according to the Felder-Solomon LearningStyle Index. (e.g. global/sequential, active/reflective, verbal/visual andsensing/intuitive)

* Publisher: Prentice Hall PTR
* Number Of Pages: 1120
* Publication Date: 2005-09-02
* ISBN-10 / ASIN: 0130473944
* ISBN-13 / EAN: 9780130473943
* Binding: Hardcover

Download:
Rapidshare
Rapidshare

Selengkapnya...

by Max Stone Peters
Product Description:
A revision of the classic text-reference for the chemical engineering "design" course usually offered to all Chemical Engineers at the junior/senior level. This new edition contains the latest cost data as well as new emphasis on safety and H42OPS and a new chapter on Computer-Aided Design. The book nicely balances both economics (cost estimating and cost data) and process equipment design in one text.

* Publisher: McGraw-Hill Companies
* Number Of Pages: 992
* Publication Date: 1990-07-01
* ISBN-10 / ASIN: 0070496137
* ISBN-13 / EAN: 9780070496132
* Binding: Hardcover

Download:
Rapidshare
File Factory


Selengkapnya...

by Gavin Towler, R K Sinnott
Product Description:
''Bottom line: For a holistic view of chemical engineering design, this book provides as much, if not more, than any other book available on the topic.' Extract from Chemical Engineering Resources review.

Chemical Engineering Design is a complete course
text for students of chemical engineering. Written for the Senior Design Course, and also suitable for introduction to chemical engineering courses, it covers the basics of unit operations and the latest aspects of process design, equipment selection, plant and operating economics, safety and loss prevention. It is a textbook that students will want to keep through their undergraduate education and on into their professional lives.

* Provides students with a text of unmatched relevance for the Senior Design Course and Introductory Chemical Engineering Courses
* Teaches commercial engineering tools for simulation and costing
* Comprehensive coverage of unit operations, design and economics
Strong emphasis on HS&E issues, codes and standards, including API, ASME and ISA design codes and ANSI standards
* 108 realistic commercial design projects from diverse industries
* A rigorous pedagogy assists learning
, with detailed worked examples, end of chapter exercises, plus supporting data and Excel spreadsheet calculations plus over 150 Patent References, for downloading from the companion website
* Extensive instructor resources: 1170 lecture slides on CD plus fully worked solutions manual

* Publisher: Butterworth-Heinemann
* Number Of Pages: 928
* Publication Date: 2007-11-01
* ISBN-10 / ASIN: 0750684232
* ISBN-13 / EAN: 9780750684231
* Binding: Hardcover

Download:
Rapidshare
mihd.net
Mediafire



Selengkapnya...

by STAN WALAS
Product Description:
Chemical Process Equipment
is a guide to the selection and design of a wide range of chemical process equipment. Emphasis is placed on specific information concerning the process design and performance of equipment. To this end, attention is given to examples of successful applications, and a generous number of line sketches showing the functioning of equipment is included with many graphs and tables giving their actual performance. For coherence, brief reviews of perininent theory, including numerical examples to illustrate the more involved procedures, are provided in key chapters.

Professor Walas, drawing up on his many years of experience in industry and academia, provides a wealth of valuable shortcut methods, rules of thumb, and design by analogy applications. References to sources of more accurate design procedures are cited whenever they are available. To illustrate the data essential to process design, a substantial number of equipment rating forms and manufacturers' questionnaires have been collected. Because decisions often must be based on economic grounds, a short chapter on costs of equipment rounds out the book.

Serves as a guide for selecting and designing chemical process equipment.
Provides numerous examples with many graphs and tables.
Includes a chapter on equipment cost to address important economic concerns.
* Publisher: Butterworth-Heinemann
* Number Of Pages: 755
* Publication Date: 1988-10-04
* ISBN-10 / ASIN: 0750693851
* ISBN-13 / EAN: 9780750693851
* Binding: Hardcover

Download:
mihd.net


Selengkapnya...